Telex Stereo Amplifier MCE325 User Manual

USER INSTRUCTIONS  
MODEL MCE325  
PROGRAMMABLE USER STATION  
9350-6464-00 Rev J, 7/2001  
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RETURN SHIPPING INSTRUCTIONS  
PROCEDURE FOR RETURNS  
If a repair is necessary, contact the dealer where this unit was purchased.  
If repair through the dealer is not possible, obtain a RETURN AUTHORIZATION from:  
Customer Service Department  
Telex Communications, Inc.  
Telephone: (877) 863-4169  
Fax: (800) 323-0498  
DO NOT RETURN ANY EQUIPMENT DIRECTLY TO THE FACTORY WITHOUT FIRST OBTAINING A  
RETURN AUTHORIZATION.  
Be prepared to provide the company name, address, phone number, a person to contact regarding the repair, the type  
and quantity of equipment, a description of the problem and the serial number(s).  
SHIPPING TO MANUFACTURER FOR REPAIR OR ADJUSTMENT  
All shipments of RTS products should be made via United Parcel Service or the best available shipper, prepaid. The  
equipment should be shipped in the original packing carton; if that is not available, use any suitable container that is  
rigid and of adequate size. If a substitute container is used, the equipment should be wrapped in paper and surrounded  
with at least four inches of excelsior or similar shock-absorbing material. All shipments must be sent to the following  
address and must include the Return Authorization.  
Factory Service Department  
Telex Communications, Incorporated  
West 1st Street  
Blue Earth, MN 56013 U.S.A.  
Upon completion of any repair the equipment will be returned via United Parcel Service or specified shipper collect.  
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End-User License Agreement for Telex® Software  
IMPORTANT - Please read this document carefully before using this product.  
THIS DOCUMENT STATES THE TERMS AND CONDITIONS UPON WHICH TELEX COMMUNICATIONS,  
INC. (the “COMPANY”) OFFERS TO LICENSE THE INSTALLED SOFTWARE OR PROGRAM (the “SOFT-  
WARE”) FOR USE WITH THE PRODUCT IN WHICH IT WAS INSTALLED. YOU ARE AGREEING TO  
BECOME BOUND BY THE TERMS OF THIS AGREEMENT. IF YOU DO NOT AGREE TO THE TERMS OF  
THIS AGREEMENT, DO NOT USE THIS PRODUCT. PROMPTLY RETURN THE PRODUCT TO THE  
PLACE WHERE YOU OBTAINED IT FOR A FULL REFUND.  
The installed software as supplied by the Company is licensed, not sold, to you for use only under the terms of this  
license, and the Company reserves all rights not expressly granted to you. You own the product or other media on or  
in which the Software is originally or subsequently recorded or fixed, but the Company retains ownership of all  
copies of the Software itself.  
1. License: This license allows you to use the Software for internal purposes only on a single product in which it  
was installed.  
2. Restrictions: (a) You may not market, distribute or transfer copies of the Software to others or electronically  
transfer or duplicate the Software. YOU MAY NOT REVERSE ENGINEER, DECOMPILE, DISASSEMBLE,  
MODIFY, ADAPT, TRANSLATE, RENT, LEASE OR LOAN THE SOFTWARE OR CREATE DERIVATIVE  
WORKS BASED ON THE SOFTWARE OR ANY ACCOMPANYING WRITTEN MATERIALS. (b) The Soft-  
ware and the accompanying written materials are copyrighted. Unauthorized copying of the Software, including  
portions thereof or the written materials, is expressly forbidden. (c) You understand that the Company may update  
or revise the Software and in so doing incurs no obligation to furnish such updates to you.  
3. Limited Warranty: The Company does not warrant that the operation of the Software will meet your require-  
ments or operate free from error. The Company DISCLAIMS ALL OTHER WARRANTIES AND CONDITIONS  
EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY, FITNESS  
FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS.  
4. Limited Liability: The liability of the Company for any claims arising out of this License based upon the Soft-  
ware, regardless of the form of action, shall not exceed the greater of the license fee for the Software or $50.  
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TABLE OF CONTENTS  
i
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ii  
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iii  
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iv  
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S E C T I O N  
C
HAPTER1  
DESCRIPTION & SPECIFICATIONS  
Description  
General  
The MCE325 is a four-channel, programmable intercom station. It may be used as a headset  
station or, with the addition of the MCS325 Modular Speaker, as a speaker station. It may be  
mounted in a console or equipment rack via optional mounting kits.  
The MCE325 can be used with either two-wire or four-wire intercom lines, or a combination of  
both. In this manual and in the labeling on the MCE325, references to channels 1, 2, 3, and 4  
indicate two-wire lines; references to four-wire A and four-wire B indicate four-wire lines.  
The MCE325 can be interfaced to a variety of external devices including external program  
sources, two-way radios, paging systems, and satellite circuits. Some typical applications are  
Features  
Features of the MCE325 include:  
• Call Signaling: Call signaling is accomplished using an inaudible (20 kHz) signal to activate a  
call indicator LED.  
• Remote “talk-off”: Active, unattended remote station microphones may be deactivated by  
momentarily injecting an inaudible (24 kHz) signal into the corresponding intercom line. The  
MCE325 can send and receive “talk-off” signals.  
• VOX circuit: The MCE325 may be programmed for voice activation of the microphone.  
• Simple IFB: Program audio assigned to a channel is interrupted during talk.  
• External device keying: External devices, such as two-way radios, speaker mute relays, or  
paging systems may be activated through key outputs at the auxiliary connector on the rear  
panel. The key outputs may also be used to expand the simple IFB function, allowing any one  
of a number of MCE325 stations to interrupt the program source and talk on the line.  
• Microphone limiter: The microphone preamplifier circuit contains a limiter, which helps to  
equalize voice levels.  
• Fully programmable: Retains programming even when power is shut off.  
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Front Panel Features  
Channel Selector and Operation Buttons  
These buttons have two modes of operation: standard operating mode and program, or setup,  
mode. The printing on the face of each button indicates its function in standard operating mode;  
printing under each button indicates its setup mode function. (See Section 3 for operation and  
programming instructions.) An LED located above each button provides status information.  
The MCE325 is factory pre-programmed for two-channel operation, with each channel having  
one talk and one listen button. However, the MCE325 may also be programmed so that each  
channel selector button controls both talk and listen for a single channel, permitting operation of  
up to four intercom channels. Additionally, users may wish to customize the identification of  
channels. With this in mind, a button kit has been supplied with the MCE325 to allow you to  
customize the button labeling to suit your particular application. Figure 1.11 shows the available  
button caps as well as some typical button configurations.  
NOTE The standard buttons are opaque. As a result, the front panel LED’s may not be visible when  
viewing the MCE325 from a low angle (such as when it is mounted high in an equipment rack).  
As a remedy for this problem, clear buttons are available that allow the LED light to pass through.  
(Order RTS™ part no. 9000-2698-800)  
Volume Controls  
CH1 (VOL 1): This control adjusts the volume of channels 1 and/or 3 to the left headphone when  
stereo headphones are used. It adjusts the mono mix level of these channels when monaural  
headphones or an external speaker is used.  
CH2 (VOL 2): This control adjusts the volume of channels 2 and/or 4 to the right headphone  
when stereo headphones are used. It adjusts the mono mix level of these channels when monaural  
headphones or an external speaker is used.  
PGM VOL: This control adjusts the mono mix of program A and program B (input at the rear  
panel and assigned via internal programming) to the headphones and external speaker.  
Sidetone Nulling Trimmers  
These trimmers are adjusted to prevent acoustic feedback when using a panel microphone along  
with an external speaker.  
Connections, Inputs and Outputs  
Front Panel  
DYNamic MIC HEADSET: This connector accepts a stereo-earphone, dynamic-microphone  
headset (with or without a mic on/off switch).  
CARBon MIC HEADSET: This connector accepts a standard 3-conductor, ¼-inch phone plug.  
The necessary phantom power is provided to power a carbon microphone or its electronic  
equivalent.  
Panel Microphone Jack  
The MCE325 may be optionally fitted with a gooseneck panel microphone by removing the  
blanking plug located in the upper-right corner of the front panel. The panel microphone jack  
accepts specially made gooseneck microphones (MCP-90 series), which are available from RTS.  
1-2 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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Figure 1.1 MCE325 front and rear panel features.  
Rear Panel Features  
Intercom Lines  
Connectors J8 and J9 are parallel-wired for loop-through connection to additional stations. These  
connectors are used either for two-wire channels 1 and 2 input/output, or four-wire channel A  
output. (The four-wire channel A input is connected at the auxiliary connector.)  
Connector J10 is used for two-wire channel 3 and 4 input/output, or four-wire channel B output,  
but no loop-through connector is provided for these channels. (The four-wire channel B input is  
connected at the auxiliary connector.)  
The MCE325 presents a bridging impedance of 10,000 ohms to the intercom line, and is designed  
for use with intercom lines having a 200-ohm line terminating impedance. A 200 ohm termination  
plug is supplied (connected to J10) to prevent channels three and four from oscillating when the  
MCE325 is in two-channel mode.  
External Program Input  
Two ¼-inch phone jacks are provided for external program input. The station accepts line-level,  
balanced input. The two program inputs are mixed internally, and may be assigned (through  
internal programming) to right headphone, left headphone, external speaker, or any combination  
of these. In addition, program A may be assigned (through internal programming) to two-wire  
channel 3 or four-wire channel A; program B may be assigned to two-wire channel 4, but cannot  
1-3  
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be assigned to a four-wire channel. The program assigned to channels is interrupted during talk  
output.  
Speaker Output  
A ¼-inch phone jack is provided for connection of an external speaker (8-ohms minimum  
impedance). The speaker output is compatible with the MCS325 speaker.  
Auxiliary Connector  
Standard Options on the 25-pin, female, D-Sub connector are:  
1 Unswitched microphone output  
2 ISO connection to a VCP6A/VCP12A/VCP12B  
3 Microphone on/off switch  
4 Remote headset  
5 Remote panel microphone  
6 Separate inputs for +10 to +15 volts DC, and +17 to +24 volts DC  
7 Common/ground circuit  
8 Four-wire channel A and B inputs  
9 Remote speaker mute  
10Key outputs  
Programming  
Three methods of programming are used:  
1 Front panel programming via the channel selector and operation buttons.  
2 Internal programming via circuit board DIP switches.  
3 Internal programming via circuit board jumpers.  
The most commonly programmed options are assigned to the front panel for convenience.  
Detailed information on internal programming is provided in Section 2, Installation. Detailed  
information on front panel programming is provided in Section 3, Operation.  
Power  
The MCE325 is designed for local powering, and is supplied ready for use with either 115 or 230  
VAC (but not both). The unit may also be powered from an external DC source connected at the  
Auxiliary (J22) connector on the rear panel. For information on changing the AC supply voltage  
configuration, or using DC power, see Section 2.  
Mounting Configuration  
Mounting configurations are illustrated in Figure 2.3 and include rack mount speaker station,  
console mount headset station, rack mount headset station, desk top headset station, and portable  
speaker station. Some mounting configurations may require a remotely located microphone or  
headset. These may be connected to the Auxiliary connector (J22) on the back of the unit.  
1-4 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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MCE325 Specifications  
General  
Bridging Impedance (to line)  
Noise Contribution to 200-ohm Line  
Call Signal Frequency  
10,000 ohms typical  
-90 dBu  
20 kHz, crystal controlled  
24 kHz, crystal controlled  
Talk-off Frequency  
Microphone Preamplifier  
Maximum Voltage Gain  
Frequency Response  
Input Impedance  
54 dB  
100 Hz to 8,000 Hz, 3 dB  
1,000 ohms  
Limiter Range  
30 dB  
Headphone Amplifier  
Maximum Voltage Gain  
Frequency Response  
Headphone Impedance  
Output Power  
30 dB  
100 Hz to 8,000 Hz, 3 dB  
50 to 600 ohms  
150 mW into 50 ohms  
8 Vp-p  
Output Voltage Level  
Speaker Amplifier  
Maximum Voltage Gain  
Frequency Response  
30 dB  
100 Hz to 8,000 Hz, 3 dB  
8 to 16 ohms  
5W into 8 ohms  
16 Vp-p  
Speaker Impedance  
Output Power per Amplifier  
Output Voltage Level  
Power and Mechanical  
Power Requirements  
115 to 230 VAC, 20 VA max,  
12 to 25 VDC, 100 to 125 mA quiescent, 900 mA max  
Dimensions  
Weight  
1.72” H x 8.2” W x 8” D (44 mm x 208 mm x 203 mm)  
4.25 lbs (1.93kg)  
Material/Finish  
finish  
Thermo-plastic front panel, aluminum case, light gray  
1-5  
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Connectors  
Intercom Line Connector  
XLR type, 3-pin (male-female loop through on two-wire  
channel 1 and 2, or four-wire channel A; Female only on  
two-wire channel 3 and 4, or four-wire channel B  
Dynamic Mic  
Carbon Mic  
XLR type, 6-pin female  
¼-inch phone jack, 3-circuit  
25-pin, female, D-Sub  
Auxiliary Connector  
Program Inputs  
Speaker Output  
Panel Mic  
¼-inch phone jack, 3-circuit  
¼-inch phone jack, 3-circuit  
¼-inch phone jack, metal busing, 3-circuit  
MCS325 Specifications  
The MCS325 is designed for use with MCE325, but may also be used as a general-purpose  
monitor for program material.  
Impedance  
Power Rating  
Sensitivity  
8 ohms (DCR5.5 to 7 ohms)  
5W RMS continuous  
90 dB 2 dB/2.83 volts/one meter on axis averaged over  
one octave bands centered at 250 Hz, 500 Hz, 1 kHz,  
2 kHz, 4 kHz, and 8 kHz when enclosed in a sealed box  
of 1.3 liters volume.  
Frequency Response  
200 Hz to 10 kHz 4 dB on 1/10 octave measurement in  
1.3 liter sealed box.  
Free Air Resonance  
Distortion  
200 Hz to 250 Hz  
Less than 10% @ 5W at resonance.  
Less than 1 gauss at 1 cm from chassis.  
Stray Magnetic Field  
Mechanical Noise  
Unit to be free of buzzes and rattles at 5 W sine wave  
input from 100 Hz to 10 kHz.  
Figure 1.2 Standard two-channel, two-wire configuration.  
1-6 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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Figure 1.3 Standard four-channel, two-wire configuration.  
Figure 1.4 A four-channel, two-wire configuration with two channels used for IFB’s.  
Figure 1.5 Configuration for one or two two-wire channels and one four-wire channel.  
1-7  
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Figure 1.6 Standard two-channel, four wire configuration.  
Figure 1.7 Multiple interconnected stations in four-channel, two-wire configuration with two channels  
used for IFB’s.  
1-8 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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Figure 1.8 Multiple interconnected stations using one four-wire intercom channel and two two-wire  
channels for IFB’s.  
Figure 1.9 A four-channel, two-wire configuration with two channels used for IFB’s (shown with TELCO  
interface).  
1-9  
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Figure 1.10 Configuration for an ENG truck using one four-wire intercom channel and two two-wire  
IFB’s.  
1-10 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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Figure 1.11 MCE325 button configurations.  
1-11  
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1-12 M C E 3 2 5 U s e r I n s t r u c t i o n s  
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S E C T I O N  
C
HAPTER2  
INSTALLATION  
Internal Programming and Adjustments  
WARNING  
Hazardous voltages exist inside this equipment. Disconnect the AC line cord before  
opening the equipment or attempting any internal programming or adjusting.  
General  
Prior to installing the MCE325, it may be necessary to change some of the internal programming  
to suit your particular application. Table 2.1 and Table 2.2 list the functions for the DIP switches  
and jumpers which are used for internal programming. Also shown are the default settings that  
were pre-programmed at the factory.  
If your application requires settings that are different from the defaults, you will have to remove  
the top cover of the unit (see Figure 2.1) and make the required changes. If you do change the  
internal programming, it may be useful to note the changes for future reference.  
The locations of the DIP switches and jumpers are illustrated in Figure 2.2. DIP switch  
programming is accomplished by setting switches to the “off” or “on” positions. Jumper  
programming is accomplished using shorting jumpers. By inserting the jumpers to short the  
appropriate pins, a function is either assigned or not assigned. Pin 1 of each jumper is indicated by  
a square symbol in Figure 2.2 for reference when making changes. Also shown in Figure 2.2 are  
trimmers for adjusting the sidetone and speaker dimming levels. Usage of the DIP switches,  
jumpers, and level trimmers is described in the following paragraphs.  
2-1  
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Figure 2.1 Top cover removal.  
Intercom Line-Channel Configurations (DS1-DS3, J6, J7, J19 & J20)  
The four channels of the MCE325 may be assigned to intercom lines in a variety of ways.  
Channel assignment is determined by the settings of DIP switches DS1 through DS3 and jumpers  
J6, J7, J19, and J20. There are six possible intercom line configurations. These are listed in Table  
2.3 together with the proper DIP switch and jumper settings for each.  
Table 2.1 DIP switch functions and default settings.  
Switch Number Switch Function  
Default Setting  
DS1  
four-wire CH A output not installed (off), four-wire CH A output installed Off  
(on)  
DS2  
four-wire CH B output not installed (off), four-wire CH B output installed Off  
(on)  
DS3  
DS4  
two-channel mode (off)*, four-channel mode (on)  
Off  
Off  
Front panel setup lock-out disabled (off), Front panel setup lock-out  
enabled (on)  
DS5  
DS6  
DS7  
DS8  
Listen and talk muted during ISO (off), Talk only muted during ISO (on) Off  
Not used  
Off  
On  
Off  
Talk-off transmit disabled (off), Talk-off transmit enabled (on)  
VOX disabled (off), VOX enabled (on)  
NOTE The terms “two-channel mode” and “four-channel mode” apply only to two-wire lines. In two-  
channel mode, each two-wire line uses two channel selector buttons: one for talk and one for  
listen. In four-channel mode, each two-wire line uses one channel selector button for both talk and  
listen.  
The two-channel mode should be selected under only two circumstances:  
1 When only one or two two-wire lines are connected to channels one and two only.  
2-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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2 When a two-wire line is connected to channel one and a four-wire line is connected to channel  
B.  
For all other intercom line configurations that use two-wire lines, DS3 must be set to the “on”  
position for four-channel operation.  
Table 2.2 Jumper functions and default settings.  
Jumper Number Jumper Function  
Default Setting  
J4  
J5  
J6  
Assigns PROGRAM A input to two-wire CH 3 or four-wire CH B. Not assigned  
Not assigned: pins 2 & 3 shorted.  
Assigned: pins 1 & 2 shorted (IFB to CH 3).  
Assigns PROGRAM B input to two-wire CH 4.  
Not assigned: pins 2 & 3 shorted.  
Not assigned  
Assigned: pins 1 & 2 shorted (IFB to CH 4).  
Selects two-wire CH1 and CH 2, or four-wire CH A output. (See J19 Two-wire operation  
for CH A input.)  
CH1 and CH 2 selected: pins 2 & 3 shorted.  
Four-wire CH A output selected: pins 1 & 2 shorted.  
J7  
Selects two-wire CH 3 and CH 4, or four-wire CH B output. (See J20 Two-wire operation  
for Ch B input.)  
CH 3 and CH 4 selected: pins 2 & 3 shorted.  
Four-wire CH B output selected: pins 1 & 2 shorted.  
J16  
J17  
Assigns mono mix of the PROGRAM A and B inputs to the left  
headphone.  
Not assigned: pins 2 & 3 shorted.  
Assigned: pins 1 & 2 shorted.  
Assigned  
Assigned  
Assigns mono mix of the PROGRAM A and B inputs to the right  
headphone.  
Not assigned: pins 2 & 3 shorted.  
Assigned: pins 1 & 2 shorted.  
J18  
J19  
J20  
J24  
Assigns mono mix of the PROGRAM A and B inputs to the speaker. Assigned  
Not assigned: pins 2 & 3 shorted.  
Assigned: pins 1 & 2 shorted.  
Selects four-wire CH A input. Off (not used): pins 2 & 3 shorted.* Off  
On when LISTEN 1 button is on: pins 1 & 2 shorted.  
Always on: pins 3 & 4 shorted.  
Selects four-wire CH B input. Off (not used): pins 2 & 3 shorted.*  
On when LISTEN 2 button is on: pins 1 & 2 shorted.  
Always on: pins 3 & 4 shorted.  
Off  
Selects unbalanced or balanced dynamic mic input.  
Unbalanced: pins 2 & 3 shorted.  
Unbalanced mic input  
Balanced: pins 1 & 2 shorted.  
NOTE *J19 and J20 jumpers should be in “off” positions when two-wire lines are used.  
2-3  
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Figure 2.2 Internal DIP switches, jumpers and level trimmers.  
2-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 2.3 Internal programming for the various intercom line configurations.  
DIP SWITCHES JUMPERS  
DS1 DS2 DS3 J6  
Configuration 1: Two 2-wire lines (CH 1& CH 2). (Default configuration.)  
Off Off Off Pins 2 & 3 shorted Pins 2 & 3 shorted Pins 2 & 3 shorted Pins 2 & 3 shorted  
Configuration 2: Three or four 2-wire lines (CH 1, CH 2, CH 3, CH 4).  
Off Off On Pins 2 & 3 shorted Pins 2 & 3 shorted Pins 2 & 3 shorted Pins 2 & 3 shorted  
Configuration 3: One 2-wire line (CH 1); One 4-wire line (CH B).  
Off On Off Pins 2 & 3 shorted Pins 1 & 2 shorted Pins 2 & 3 shorted Pins 1 & 2 shorted  
Configuration 4: Two 2-wire lines (CH1 & CH2); One 4-wire line (CH B).  
Off On On Pins 2 & 3 shorted Pins 1 & 2 shorted Pins 2 & 3 shorted Pins 1 & 2 shorted  
Configuration 5: Two 2-wire lines (CH 3 & CH4); One 4-wire line (CH A).  
On Off On Pins 1 & 2 shorted Pins 2 & 3 shorted Pins 1 & 2 shorted Pins 2 & 3 shorted  
Configuration 6: Two 4-wire lines (CH A & CH B).  
On On On Pins 1 & 2 shorted Pins 1 & 2 shorted Pins 1 & 2 shorted Pins 1 & 2 shorted  
J7  
J19  
J20  
NOTE See Table 3.1for a summary of how the channel selector buttons work for the various  
configurations. The MCE325 is typically supplied with a termination plug inserted into J10. This  
plug terminates CH 3 and CH 4 with 200 ohms to prevent oscillation when these channels are not  
used. When the channels are used, this termination plug should be removed.  
Front Panel Setup Mode Lock-out (DS4)  
DIP switch DS4 may be set to lock out the front panel programming and prevent changes. Front  
panel programming is described in Section 3, Operation.  
ISO (DS5)  
The MCE325 may be used with an RTS Model VCP6A, VCP12A, or VCP12B Control Station to  
permit private conversation between the MCE325 operator and a camera operator. When ISO  
mode is engaged, either talk, or talk and listen (depending on the setting of DS5) for all other  
channels connected to the MCE325 will be muted, and a private line will be established between  
the MCE325 operator and the camera operator. See “ISO Connection” for wiring information.  
Remote Talk-off (DS7)  
The MCE325 is capable of generating and transmitting an inaudible, 24 kHz signal on an  
intercom channel. This signal is used to turn off the microphones on any remote stations on the  
channel (stations with remote talk-off feature only). This feature is useful when an unattended  
user station with an activated microphone is introducing unnecessary noise into a line. DIP switch  
DS7 enables/disables this feature. When remote talk off is enabled, the talk-off signal is activated  
using the CALL button on the front panel. (for Operation see “Using the Talk-Off Feature”.)  
VOX (DS8)  
DIP switch DS8 turns the voice activated microphone circuit on or off. Voice activation can be  
used with the panel microphone, a headset, or a remote microphone connected at the rear panel.  
(There is no adjustment for VOX sensitivity.)  
2-5  
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Program Assignment – IFB Option (J4, J5, J16-J18)  
Jumper J4 assigns PROGRAM A to two-wire CH 3 or four-wire CH B with interrupt during talk  
(IFB A). Jumper J5 assigns PROGRAM B to CH 4 with interrupt during talk (IFB B).  
(PROGRAM B is not used in four-wire mode.)  
Jumpers J16, J17, and J18 assign the mono mix of both program inputs to the left headphone,  
right headphone, and speaker respectively. Program volume to the headphones and speaker is  
controlled by the PGM VOL control on the front panel.  
See Table 2.2 for Jumper settings. See Figure 2.2 for locations of jumpers.  
Balanced/Unbalanced Dynamic Microphone Selection (J24)  
The MCE 325 may be used with headsets having either a balanced or unbalanced dynamic  
microphone. The MCE325 is pre-programmed for use with an unbalanced microphone by  
shorting J24 pins 2 and 3. For balanced microphones, remove the shorting jumper and reinstall it  
to short pins 1 and 2.  
Headphone Sidetone Trimmer Adjustment (R37)  
The headphone sidetone trimmer (R37) adjusts the loudness of your own voice heard in your  
headset when the microphone is on and the speaker is off. (It does not affect the actual level heard  
on the intercom lines.) This trimmer is preset so that your voice level in the headphones will be  
approximately ¾ of the intercom line level. To prevent feedback, this signal is automatically  
turned off when the external speaker is turned on with the SPKR ON switch.  
Speaker Dim Adjustment (R157)  
When an external speaker is used, switching the microphone on will cause the speaker level to  
attenuate. The level of attenuation may be adjusted with the speaker dim trimmer (R157). The  
minimum attenuation of 6 dB is preset at the factory (R157 fully clockwise). The range of  
adjustment is –6 dB to –40 dB.  
Mechanical Installation  
Dimensional requirements for the various mounting configurations are illustrated in Section 6.  
Also allow an additional 4.0 inches (102 mm) of rear panel clearance for connectors.  
If the headset connector is remotely located (See “External Headset”), allow space between the  
cable and interfering sources such as TV monitors, power supplies and equipment with internal  
power supplies. The MCE325 has no special ventilation space requirements.  
Assembly of optional mounting components is shown in Figure 2.3.  
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Figure 2.3 Mounting configurations.  
2-7  
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Electrical Installation  
AC Power and Fuse  
The Model MCE325 is pre-wired for either 115 or 230 VAC operation, and the appropriate fuse is  
already installed. The MCE325 uses a 0.5A Slo-Blo fuse for 115 volt operation, or a 0.25A Slo-  
Blo fuse for 230 volt operation. (A fused external DC source may be used instead of AC power if  
desired. (See “External DC Power Source”.)  
Intercom Lines J8, J9, and J10  
General  
Intercom line connectors J8 and J9 are parallel-wired for loop-through connection to other  
intercom stations. These connectors are used for connection of two-wire lines to channels one and  
two (full-duplex operation), or for connection of four-wire channel A output (channel A input is  
connected at the auxiliary connector).  
Intercom line connector J10 is used for connection of two-wire lines to channels three and four  
(full-duplex operation), or for connection of four-wire channel B output (channel B input is  
connected at the auxiliary connector).  
Connector Pin-outs  
Table 2.4 Connectors J8 and J9.  
PIN # FUNCTION  
1
2
3
Common (low side of line)  
Two-wire CH 1 or four-wire CH A high output  
Two-wire CH 2 or four-wire CH A low output  
Table 2.5 Connection J10  
PIN # FUNCTION  
1
2
3
Common (low side of line)  
Two-wire CH 3 or four-wire CH B high output  
Two-wire CH 4 or four-wire CH B low output  
Four-wire Output Termination  
Figure 2.4 4-wire output terminations.  
When four-wire outputs are used, termination resistors must be installed for proper operation. The  
output amplifiers are current sources, and the output level is determined by the terminating  
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resistor values. These resistors would normally be installed in the cable connector, but may be  
placed at any point in the signal path. Recommended values are shown in X.  
Program Inputs, J14 and J15  
The PROGRAM A and B inputs accept line-level (0 dBu nominal), balanced audio. The program  
inputs are connected using ¼-inch stereo phone plugs.  
Figure 2.5 Connectors J14 and J15.  
SECTION  
FUNCTION  
Tip  
Program high  
Program low  
Common  
Ring  
Sleeve  
The MCE325 must be internally programmed to assign the program inputs to the intercom lines,  
headphones, or speaker output (see “Program Assignment”). Program volume to the headphones  
and speaker is controlled by the PGM VOL control on the front panel.  
External Speaker, J27  
The SPEAKER OUTPUT jack provides a bridging-type output for an external speaker (8 ohms  
minimum). The external speaker is connected using a ¼-inch phone plug.  
Figure 2.6 Connector J27.  
SECTION  
FUNCTION  
Tip  
Speaker plus  
Speaker minus  
No connection  
Ring  
Sleeve  
CAUTION The MCE325 provides a bridging-type speaker output. DO NOT LET EITHER SPEAKER  
LEAD CONTACT GROUND.  
The external speaker is turned on and off by the front panel SPKR ON switch.  
Auxiliary Connector, J22  
Four-Wire Channel A and B Input  
The four-wire channel A and channel B inputs are connected at the auxiliary connector as  
follows:  
Table 2.6 Auxiliary connector, J22.  
PIN # FUNCTION  
8
Four-wire channel A high  
Four-wire channel A low  
Four-wire channel B high  
Four-wire channel B low  
21  
9
22  
The four-wire inputs must be assigned, using internal programming jumpers J19 and J20, before  
they can be used (as previously described in “Intercom Line-Channel Configurations (DS1-DS3,  
J6, J7, J19 & J20).”  
2-9  
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Key outputs – Expanded IFB Option  
Four logic-type outputs are available at pins 6, 7, 19, and 20 of the auxiliary connector:  
Table 2.7 Auxiliary connector, J22.  
PIN # FUNCTION  
6
CH 1 or four wire CH A key output  
CH 3 or four-wire CH B key output  
CH 2 key output  
7
19  
20  
CH 4 key output  
There are internal pull-up resistors on the CH 3 and CH 4 key outputs. Pressing the CH 3 or CH 4  
talk button will result in a logic high to low transition at the corresponding key output. (Logic  
high is approximately 13 VDC; Logic low is less than 2 VDC.) There are no internal pull-up  
resistors on the CH 1 and CH 2 key outputs. These outputs will “float” until externally loaded.  
The channel three and four key outputs may also be used to expand the IFB function, allowing  
any one of several MCE325 User Stations to interrupt a single-point program source and talk on  
the interrupted channel. For example, if one MCE325 is operating with PROGRAM A assigned to  
channel three, the channel three key output of a second MCE325 User Station (with no program  
connected) can be directly connected to the channel three key output of the first MCE325;  
activating channel three for talk from either station will now interrupt the program source and  
permit that station to talk on channel three.  
Remote Microphone Switch  
A remote microphone switch may be connected at the auxiliary connector. Connect mic switch  
high to pin 25; connect mic switch low to pin 10 or 11. When the switch is closed, the microphone  
will turn on, and the front panel MIC ON LED will illuminate. When the remote switch is off, the  
microphone may be turned on from the front panel. When the remote switch is on however, the  
microphone cannot be turned off from the front panel.  
ISO Connection  
To connect an RTS Model VCP6A, VCP12A, or VCP12B ISO Control Panel to the MCE325,  
connect the unswitched microphone output of the MCE325 (pins 1 and 14 of the auxiliary  
connector) to the four-wire input of the VCP Control Panel; connect the four-wire output of the  
VCP Control Panel to either a four-wire input or a program input of the MCE325; connect the  
logic contact output of the VCP Control Station to the ISO input of the MCE325 (pin 12 of the  
auxiliary connector); connect VCP common to pin 11 of the auxiliary connector.  
External Headset  
An external headset may be connected to the auxiliary connector. (See “Headset Requirements”.)  
Connect headphone left to pin 5, headphone right to pin 18, and headphone common to pin 17.  
Connect microphone high to pin 4; connect microphone low to pin 16. The external headset  
connections are wired in parallel with the front panel dynamic headset connector; therefore, use  
only one at a time.  
In the headset connecting cable, prevent coupling between the microphone and headphone leads  
by using a shielded twisted pair for the microphone, and a separate shielded twisted pair for the  
headphones. Do not allow headphone common to contact microphone low. Tie the headphone  
shield to headphone common. The headset cable can be made longer when the microphone and  
headphone pairs are physically separated. The wider the separation, the longer the allowable cable  
length. Estimated maximum usable headphone cable lengths are as follows:  
Single cable, two shielded twisted pairs: 10 feet (3.05 m). Dual-ribbed cable, two shielded twisted  
pairs: 30 feet (9.14 m).  
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Separate shielded twisted pair cables: 50 feet (15.24 m). Balanced microphone input: up to 100  
feet (30.48 m).  
External Electret Microphone  
An external electret microphone may be connected at the auxiliary connector and used in place of  
a front-panel gooseneck microphone. Connect microphone high/bias to pin 15 and connect  
microphone low to pin 2. When using an external microphone, do not connect a front-panel  
gooseneck microphone.  
Unswitched Microphone Output  
The microphone audio is provided as an unswitched, balanced output at the auxiliary connector.  
The in-phase signal is available at pin 1; the inverted-phase is available at pin 14.  
External DC Power Source  
The MCE325 may be powered from an external DC power supply in the 10 to 25 volt range (500  
mA minimum).  
If the external supply is in the 10 to 15 volt range, connect the positive lead to pin 13 of the  
auxiliary connector and connect the minus lead to pin 10 or 11. A 0.5 Amp slo-blo fuse should be  
connected in-line for 17 to 24 volt operation.  
Remote Speaker Mute Control  
When the MCE325 is used with an external speaker, the speaker may be muted from a remote  
location. Applying a logic low signal to pin 25 of the auxiliary connector will cause muting.  
Connect circuit common to pin 11.  
Front Panel Headset Connections  
Headset Requirements  
Use headphones with an impedance of 25 ohms or greater. Low impedance 8 ohm headphones are  
not recommended. Headphones with good acoustic isolation (20 to 40 dB) improve  
communication in high ambient noise environments, and allow the user to use the headphones at a  
less tiring, lower volume.  
Headset Connections  
Dynamic-microphone headset connector: XLR-6 type receptacle.  
Table 2.8 Dynamic-microphone headset connector.  
PIN # FUNCTION  
1
2
3
4
5
6
Balanced mic low/unbalanced mic common  
Balanced/unbalanced mic high  
Headphone/mic switch common  
Headphone left  
Headphone right  
Mic Switch high  
2-11  
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Carbon-microphone headset connector: ¼-inch, tip-ring-sleeve phone jack.  
Table 2.9 Carbon-microphone headset connector.  
SECTION FUNCTION  
Tip  
Carbon microphone  
Headphone  
Ring  
Sleeve  
Common/ground  
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S E C T I O N  
C
HAPTER3  
OPERATION  
General  
The front panel buttons have different functions when the MCE325 is switched from operating  
mode to setup mode. Legends on the buttons indicate their operating mode functions; legends  
under the buttons indicate their setup mode functions. All of the front panel buttons were pre-  
programmed for a certain type of operation. This is the default configuration. Operation for the  
default configuration is described first, and is then followed by front panel programming  
instructions to alter the operation.  
Operating Instructions  
Momentary/Latching Button action  
The channel selector buttons and the MIC ON button feature a special momentary/latching dual-  
action: if a button is pressed and released quickly it will “latch” (turning “on” if off or turning  
“off” if on); if the button is pressed and held slightly longer, the action will be momentary and the  
button will turn off when released. All other buttons are latching-only (press to activate, press to  
release).  
NOTE The latching action can be disabled through the front panel programming.  
LED Indicators  
LED indicators are provided for each button to indicate current status. The LED can provide up to  
four indications: continuously off, continuously on, short blink (50% on, 50% off) and long blink  
(90% on, 10% off).  
Channel Selection  
Table 3.1 summarizes the operation of the channel selector buttons for the various intercom line  
configurations. Basically, four-wire intercom lines always use one TALK and one LISTEN  
button for intercom communication, as do two-wire lines when the station has been programmed  
for two-channel operation.  
When the station is operated in four-channel mode, however, each two-wire intercom line uses  
only one channel selector button to control both talk and listen, and the MCE325 is pre-  
programmed so that a channel is activated for both talk and listen when the button is pressed. The  
3-1  
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button action can be changed, via the front panel programming, so that the button controls talk  
only, with listen either always on or always off.  
Panel Mic/Headset Mic Selection  
The PANEL MIC button selects either panel microphone (LED on) or headset microphone (LED  
off).  
Microphone On/Off  
The MIC ON button turns the microphone on (LED on) or off (LED off).  
NOTE The MCE325 can be programmed, via the front panel, so that the microphone will automatically  
turn on whenever a channel is activated for talk. The MCE325 may also be internally  
programmed for voice-activated microphone (VOX) as previously described in Section 2.  
Speaker On/Off  
The SPKR ON button turns the external speaker on (LED on) or off (LED off).  
Volume Adjustment  
Table 3.1 summarizes the operation of the volume controls for the various intercom line  
configurations. The MCE325 is pre-programmed for stereo operation; CH 1 (VOL 1) adjusts the  
level to the left headphone and CH 2 (VOL 2) adjusts the level to the right.  
NOTE The MCE325 can be programmed, via the front panel, for monaural operation if desired.  
The PGM VOL control adjusts the monaural mix of both program inputs to both headphones and  
to the external speaker. It does not affect the program volume on the intercom lines.  
Front Panel Sidetone Nulling Trimmer Adjustment  
When the MCE325 is used with two-wire lines, the station operator’s voice signal is not only  
transmitted onto the intercom lines, but also echoed back into the MCE325 receive circuits. This  
can result in acoustic feedback when the MCE325 is used with an external speaker. The sidetone  
nulling trimmers are used to null, or subtract, the station operator’s voice signal from the rest of  
the received signal to prevent this feedback. (NOTE: This is not necessary in four-wire systems  
since transmit and receive use separate circuits.) A trimmer is provided for each of the four  
channels. The trimmers are factory-preset for maximum nulling of the microphone signal when  
an ideal 200-ohm resistance terminates each intercom channel; however, the trimmers may  
require slight readjustment after the MCE325 has been installed to compensate for variations  
from the ideal.  
To adjust the sidetone nulling trimmers:  
1 Turn the speaker switch on (even if an external speaker is not connected). This will turn off the  
internal, true sidetone trimmer (see note below).  
2 Turn on the microphone.  
3 Activate one talk button at a time, and speak into the microphone. Slowly increase the volume,  
and note the level of your voice in the headphones or speaker. Adjust the corresponding  
sidetone nulling trimmer to minimize your voice signal. Repeat for each channel being used,  
making sure that only one channel is activated at a time.  
NOTE There is also an internal, true sidetone trimmer, which allows the station operator to hear his or  
her voice when using headphones. This sidetone signal is turned off when the speaker switch is  
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turned on to prevent feedback. See “Headphone Sidetone Trimmer Adjustment (R37)” for further  
details.  
Sending and Receiving Call Signals  
To call a channel:  
1 Press the CALL button; the CALL LED’s will flash to indicate “call signal ready”.  
2 Press and hold the talk button for the channel to be called; the call signal will be transmitted as  
long as the talk button is held.  
3 When a response is received, release the talk button to turn off the call signal.  
Receiving a call:  
When there is an incoming call, the indicator LED above the appropriate channel selector button  
will flash.  
Using the Talk-Off Feature  
The talk-off feature deactivates the mic switches of all remote user stations on a selected channel.  
To use talk-off:  
1 Press and release the CALL button three times in rapid succession; the CALL LED’s will turn  
on to indicate “talk-off signal ready”.  
2 Momentarily press the talk button for the channel to be deactivated. This will cause the talk-off  
signal to be transmitted.  
3 Release the talk button to end the talk-off signal transmission.  
Front Panel Programming  
Activating Setup Mode  
Press and hold the CALL button for 5 seconds: the TALK 1, LISTEN 1, TALK 2, LISTEN 2,  
PANEL MIC, SPKR ON, and MIC ON LED’s will begin to flash. This is the main menu.  
Menu Selection/Ending Setup  
The submenu names are listed under the switches. Press the desired switch to access the submenu  
for that switch. Press the CALL button from a submenu to return to the main menu; press the  
CALL button again to exit from the main menu to the operating mode.  
NOTE If no submenu is selected from the main menu within 12 seconds after program mode activation,  
the programming mode will time out, and the MCE325 will return to normal operation. If a  
submenu is selected, however, the unit will remain in programming mode until intentionally  
exited.  
Submenus  
The following paragraphs describe each of the submenus. The default, or factory pre-programmed  
setting, is also indicated for each submenu.  
3-3  
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Channel ID  
The MCE325 can be programmed so that when someone is talking on an intercom channel, the  
corresponding listen button LED will flicker as they talk to provide a visual indication of which  
channel is talking. With the Channel ID submenu selected, press each TALK button to select or  
deselect Channel ID. The button’s LED will indicate the Selected mode as follows:  
Short LED blink: Channel ID disabled. (default).  
Long LED blink: Channel ID enabled.  
Four-channel Listen  
When the MCE325 is operating in four-channel mode, each channel selector button may be  
individually programmed for one of three types of operation. With the Four-channel Listen  
submenu activated, press each channel selector button one or more times to select the desired type  
of operation as follows:  
Short LED blink (90% on, 10% off): Button must be pressed to talk or listen (default).  
Long LED blink (50% on, 50 % off): Listen will always be on; button must be pressed to talk.  
LED off: listen will always be off; button must be pressed to talk.  
Mono  
The headphone output may be configured for either monaural or stereo operation. With the Mono  
submenu selected, press the Mono button one or more times to select the type of headphone  
output as follows:  
Long LED blink: (50% on, 50 % off): Stereo (default).  
Short LED blink: (90% on, 10 % off): Monaural.  
Call Disable  
Call disable prohibits incoming or outgoing call indication and signaling on selected channels.  
With the Call Disable submenu selected, press each talk button to select the desired operation as  
follows:  
Short LED blink (90% on, 10 % off): Call function enabled (default).  
Long LED blink (50% on, 50% off): Call function disabled.  
Button Lock  
Button lock permits all buttons (except CALL) to be individually programmed for one of three  
types of operation. With the Button Lock submenu selected, press each button one or more times  
to select the desired type of operation as follows:  
Short LED blink (90% on, 10% off): No button lock (default).  
Long LED blink (50% on, 50% off): Button locked in the “on” position.  
LED off: Button locked in the “off” position.  
Latch Disable  
Latch disable may be used to prohibit latching action for individual channel selector buttons and  
the MIC ON button. With the Latch Disable submenu selected, press each channel selector button  
or the MIC ON button one or more times to select the desired type of operation as follows:  
Short LED blink (90% on, 10% off): Latching enabled (default).  
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Long LED blink (50% on, 50% off): Latching disabled.  
Instant Mic  
Talk buttons may be individually programmed to automatically activate the microphone when  
pressed. With the Instant Mic submenu selected, press each talk button one or more times to select  
the desired type of operation as follows:  
Short LED blink (90% on, 10% off): Instant mic off (default).  
Long LED blink (50% on, 50% off): Instant mic on.  
Reset  
To restore the original programming, hold down the CH 1 talk button for about two seconds while  
powering up the MCE325.  
Table 3.1 Front panel control usage for the various intercom line configurations.  
VOLUME CONTROL USAGE CHANNEL SELECTOR BUTTON USAGE  
CH 1 (VOL 1) CH 2 (VOL 2) 1 TALK  
Configuration 1: Two -2wire lines (CH 1 & CH 2). (Default configuration.)  
CH 1 CH 2 CH 1 TALK CH1 LISTEN  
Configuration 2: Three or four 2-wire lines (CH 1, CH 2, CH 3, CH 4).  
1 LISTEN  
2 TALK  
2 LISTEN  
CH 2 TALK  
CH 2 LISTEN  
CH 1 & CH 3  
CH 2 & CH4  
CH 1 TALK &  
LISTEN  
CH 2 TALK &  
LISTEN  
CH 3 TALK &  
LISTEN  
CH 4 TALK &  
LISTEN  
Configuration 3: One 2-wire line (CH 1); One 4-wire line (CH B).  
CH 1 CH B CH 1 TALK CH 1 LISTEN  
Configuration 4: Two 2-wire lines (CH 1 & CH 2); One 4-wire line (CH B).  
CH B TALK  
CH B TALK  
CH B LISTEN  
CH B LISTEN  
CH 1  
CH 2 & CH B  
CH 1 TALK &  
LISTEN  
CH 2 TALK &  
LISTEN  
Configuration 5: Two 2-wire lines (CH 3 & CH 4); One 4-wire line (CH A).  
CH A & CH 3  
CH 4  
CH A TALK  
CH A LISTEN  
CH 3 TALK &  
LISTEN  
CH 4 TALK &  
LISTEN  
Configuration 6: Two 4-wire lines (CH A & CH B).  
CH A CH B CH A TALK  
CH A LISTEN  
CH B TALK  
CH B LISTEN  
3-5  
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S E C T I O N  
C
HAPTER4  
MAINTENANCE  
Preventive Maintenance  
Clean the unit and verify its performance periodically.  
Factory Support Information  
Factory support information is located on the first page of this manual.  
Corrective Maintenance  
WARNING: Hazardous voltages exist inside the MCE325. Attempting diagnosis, repair,  
or adjustment with the AC line connected could result in serious injury or death. These  
servicing instructions are for qualified personnel only.  
Access  
1 Reference the AS6464 drawing in section 6. Remove the four long screws (item 4) and the two  
short screws (item 5).  
2 Lift off the top cover.  
3 Pull the front panel slightly forward to clear the carbon mic jack on the main circuit board. Lift  
the front panel slightly while sliding the back panel toward the rear and out of the lower case.  
The MCE325 may now be operated for troubleshooting.  
NOTE when reassembling the bottom cover, make sure the rubber button on the inside of the bottom  
cover (item 7) is toward the front of the unit.  
Front Panel Removal  
1 Unplug the panel mic (J1) and dynamic-mic headset (J2) connectors from the main circuit  
board.  
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2 The ribbon connector from the front panel board to the main board is attached at both ends with  
locking connectors. To unlock the connector, pull the outer shell away from the circuit board.  
Then, pull the ribbon cable out.  
Cleaning  
Clean the front panel and case with alcohol or a mild solution of detergent and water, and then  
wipe off detergent residue with a damp rag. Clean the circuit board (if necessary) with a  
tetraflouroethane product such as Flux-Off® CZ by Chemtronics®. Use eye protection and avoid  
breathing the vapors with these solvents. Also, avoid getting the solvent in any of the  
potentiometers.  
Test and Adjustment Procedures  
Notes  
• All AC voltages are RMS unless otherwise specified.  
• All input and output levels were measured using an AC voltmeter calibrated for  
1 mW = 0.775V at 600 ohms, but with the 600 ohms in the circuit (0 dBu).  
• The following procedures involve changing the MCE325 programming. It may be useful to  
note the current positions of all jumpers and DIP switches so that they can be returned to their  
proper positions after testing.  
• The inside of the top cover contains a location diagram for the programming jumpers and DIP  
switches. Place it next to the MCE325 during testing for convenient reference.  
• Test procedures are written to be performed in the order presented.  
Test Equipment  
• Variac  
• 15 MHz Oscilloscope  
• AC Voltmeter  
• Frequency Counter  
• DC Voltmeter  
• Balanced Audio Generator  
• 400 Hz to 30 kHz bandpass filter with +40 dB of gain  
Power Supply Test  
1 Set a variac to 117 VAC, 60 Hz, and connect the MCE325 to the variac. Observe that each  
LED blinks on in sequence, and then all LED’s are off.  
2 Measure the voltage across the secondary of T1 (between test points E7 and E8 on the main  
circuit board).  
V
= 18 1.8 VAC  
sec  
3 Measure the DC voltage across the “+” and “-“ terminals of bridge rectifier CR1.  
= 23 2.3 VDC  
V
CR1  
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4 Measure the ripple.  
= 140 mVp-p  
V
ripple  
5 Measure the regulated DC voltage at U26 pin 2. (There should be no ripple.)  
= 13.85 0.3 VDC  
V
U26-2  
6 Measure the mid-voltage source at U17 pin 7.  
= 6.93 0.3 VDC  
V
U17-7  
7 Measure the +5 V source at the output of U27 pin 2.  
= 5.0 0.3 VDC  
V
U27-2  
Initial Configuration  
1 Set all internal jumpers and DIP switches as follows:  
DIP Switches: Set all DIP switches, except DS3, to the default settings listed in Table 2.1. Set  
DS3 to on. (This places the MCE325 in four-channel mode. Refer to Figure 1.11 for names of  
buttons in standard four-channel mode.)  
Jumpers: Set all jumpers, except J24, to the default settings listed in Table 2.2. Set J24 to the  
balanced mic position (pins 1 and 2 shorted).  
2 Connect a 200-ohm termination resistor across each of the four intercom channels:  
CH 1: J8 pins 1 and 2  
CH 2: J8 pins 1 and 3  
CH 3: J10 pins 1 and 2  
CH 4: J10 pins 1 and 3  
3 Set all front panel buttons to off.  
4 Set all volume controls to minimum.  
Keying Output Test  
1 Connect two 47 k ohm resistors: one from the key 1 output (J22 pin 6) to the +14 VDC supply;  
and one from the key 2 output (J22 pin 19) to the +14 VDC supply.  
NOTE  
The cathode of D22 serves as a convenient connection point for the +14 VDC supply. (Refer to  
the AS6245 drawing in Section 6 for the location of D22.) The key 1 and key 2 outputs require  
external pull-up resistors. The key 3 and key 4 outputs have internal pull-up resistors (RP2B  
and RP2D respectively) and do not require external pull-ups.  
Figure 4.1 Auxiliary connector, J22.  
4-3  
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2 Set the MIC ON button to on. Set all other front panel buttons to off.  
3 Check for 13 VDC minimum at the key 1 output.  
4 Turn CH 1 TALK on and check for less than 2 VDC at the key 1 output.  
5 Repeat steps 3 and 4 for the other channels:  
CH2 TALK: key 2 out (J22 pin 19)  
CH3 TALK: key 3 out (J22 pin 7)  
CH4 TALK: key 4 out (J22 pin 20)  
6 Remove the 47 kohm pull-up resistors when finished.  
USMB (Un-Switched Microphone Balanced) Frequency Response  
and Level Check  
1 Set all front panel buttons to off.  
2 Connect a signal generator to the DYN MIC HEADSET jack mic input (J2 pins 1 & 2).  
3 Connect a 600 ohm resistor across the USMB output (J22, pins 1 and 14).  
4 Connect an AC voltmeter across the 600 ohm resistor.  
5 Verify the output levels for the input frequencies and levels in Table 4.2.  
6 Remove the 600 ohm resistor across the USMB output.  
Frequency Response and Level Check, Mic to Line  
Four-Channel, Two-Wire Mode  
1 Activate the MIC ON button. (All other front panel buttons should be off.)  
2 Connect an AC voltmeter across the channel 1 output. The signal generator should still be  
connected to the dynamic mic input.  
3 Activate the CH 1 TALK button.  
4 Verify the output levels for the input frequencies and levels in Table 4.3.  
5 Repeat for channels 2 through 4 by connecting the AC voltmeter across the appropriate output,  
activating the appropriate TALK button, and measuring the output level:  
Table 4.1 Talk button vs. output.  
TALK BUTTON  
OUTPUT  
CH 2  
CH 3  
CH 4  
J8, pins 1 and 3  
J10, pins 1 and 2  
J10, pins 1 and 3  
Table 4.2 USMB frequency response and level check.  
INPUT  
FREQUENCY INPUT LEVEL  
OUTPUT LEVEL  
1 kHz  
-55 dBu (1.4 mV)  
–45 dBu (4.35 mV)  
–25 dBu (43.5 mV)  
-1 3 dBu (0.49 – 0.98 VAC)  
2.5 2 dBu (0.83 – 1.32 VAC)  
2
2 dBu (0.75 – 1.2 VAC)  
100 Hz  
-55 dBu (1.4 mV)  
–45 dBu (4.35 mV)  
–25 dBu (43.5 mV)  
-0.5 3 dBu (0.51 – 1.03 VAC)  
4.2 2 dBu (0.98 – 1.55 VAC)  
4.2 2 dBu (0.98 – 1.55 VAC)  
4-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 4.2 USMB frequency response and level check.  
10 kHz  
-55 dBu (1.4 mV)  
–45 dBu (4.35 mV)  
–25 dBu (43.5 mV)  
-5.7 3 dBu (0.28 – 0.57 VAC)  
2.2 2 dBu (0.79 – 1.26 VAC)  
2.5 2dBu (0.83 – 1.32 VAC)  
Table 4.3 Mic to line response; 4-channel, 2-wire mode.  
INPUT  
INPUT  
FREQUENCY LEVEL  
OUTPUT LEVEL  
1 kHz  
-45 dBu  
-45 dBu  
-45 dBu  
-0.8 2 dBu (0.56 – 0.89 VAC)  
-0.8 2 dBu (0.56 – 0.89 VAC)  
0.8 2 dBu (0.56 – 0.89 VAC)  
100 Hz  
100 kHz  
Two-Channel, Four-Wire Mode  
1 Remove the 200 ohm terminations from intercom channels 1 through 4.  
2 Program the MCE325 to be in two-channel, four-wire mode. (See Table 2.3, configuration 6  
for switch settings. See Figure 1.11 for names of buttons in standard two-channel mode.)  
3 Connect 200 ohm termination resistors across the four-wire A and four-wire B channels:  
Four-Wire A: J8 pins 2 and 3  
Four-Wire B: J10 pins 2 and 3  
NOTE  
Normally, the four-wire outputs would be terminated with 600 ohms for four-wire operation,  
but 200 ohms are used for testing purposes.  
4 Set the MIC ON button to on. Set all other front panel buttons to off.  
5 Connect an AC voltmeter across the Four-Wire A output.  
6 The signal generator should still be connected to the mic input. Set it to 1 kHz, -45 dBu.  
7 Activate CH 1 TALK.  
8 The output level should read –0.8 dBu 2 dBu (0.56 – 0.89 VAC)  
9 Connect the AC voltmeter across the Four-Wire B output.  
10Turn off CH 1 TALK and activate CH 2 TALK.  
11The output level should read –0.8 dBu 2 dBu (0.56 – 0.89 VAC)  
12Remove the 200 ohm termination resistors.  
Sidetone Null Test and Adjustment  
NOTE This procedure verifies sidetone null operation and optimizes nulling for an ideal 200 ohm line  
termination. Since actual intercom line impedance may vary from the ideal, the MCE325 may  
have to be readjusted slightly during actual use.  
1 Reprogram the MCE325 to be in four-channel, two-wire mode (Table 2.3, configuration 2).  
2 Reconnect 200 ohm termination resistors across each of the four intercom channels.  
3 Set the MIC ON button to on. Set all other front panel buttons to off.  
4 The signal generator should still be connected to the mic input. Set it to 1 kHz, -45 dBu.  
5 Activate the CH 1 TALK button.  
6 Monitor the AC signal level at U5 pin 7.  
7 Adjust R57 (Sidetone 1 on front panel) for maximum null (minimum signal level) at U5 pin 7.  
The signal should be 0.025 VAC or less.  
4-5  
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8 Repeat for channels 2 through 4 by activating the TALK buttons, connecting to the test points  
and adjusting the potentiometers as indicated in Table 4.4.  
True Sidetone Adjust  
1 Configure the DYN MIC HEADSET jack for stereo mode (See Section 3, “MONO”)  
2 Set all front panel buttons to off.  
3 Connect 51 ohm load resistors across the left headphone output (J2 pins 3 and 4) and right  
headphone output (J2 pins 3 and 5).  
4 Connect an AC voltmeter across the left headphone output.  
5 Remove the signal generator from the mic input, and connect it across intercom channel 1.  
Adjust the generator output to –1 dBu (0.69 VAC), 1 kHz.  
6 Activate the CH 1 TALK button, and adjust the CH 1-3 volume control (R1) until you measure  
11.2 dBu (2.82 VAC) across the left headphone output.  
7 Disconnect the signal generator from intercom channel 1. Adjust the generator for minimum  
output, and reconnect it across the DYN MIC HEADSET jack mic input (J2 pins 1 & 2).  
Readjust the generator output level to –45 dBu, 1 kHz.  
8 Turn on the MIC ON button.  
9 Adjust R37 (sidetone) on the MCE325 main board to obtain 8.7 dBu (2.1 VAC) at the left  
headphone output.  
Level and Frequency Response Check, Intercom Channel to  
Headphone  
1 Set all front panel buttons to off.  
2 Remove the signal generator from the mic input, and reconnect it across intercom channel 1.  
3 Adjust the signal generator output to –1 dBu, 1 kHz.  
4 Preset the CH 1-3 volume control to the 2 o’clock position.  
5 Activate the CH 1 TALK button. The left headphone output level should be 11.2 2 dBu (2.2  
to 3.6 VAC).  
6 Adjust the CH 1-3 volume control to measure 11.2 dBu (2.8 VAC) at the left headphone  
output. Check for no distortion or clipping in the output.  
7 Adjust the signal generator output to –1 dBu, 100 Hz. The left headphone output should read  
10.2 dBu 2 dBu (1.9 to 3.2 VAC)  
8 Adjust the signal generator output to –1 dBu, 10 kHz. The left headphone output should read  
7.8 dBu 2 dBu (1.5 to 2.4 VAC).  
9 Repeat the test for channels 2 through 4. For channel 3, continue to use the CH 1-3 volume  
control and monitor the left headphone output. For channels 2 and 4, use the CH2-4 volume  
control and monitor the right headphone output.  
Table 4.4 Channel 1-4 sidetone trimmer adjust.  
TALK BUTTON TEST POINT POTENTIOMETER  
CH 1  
CH 2  
CH 3  
CH 4  
U5 pin 7  
U5 pin 1  
U7 pin 1  
U7 pin 7  
R57 (Sidetone 1)  
R73 (Sidetone 2)  
R88 (Sidetone 3)  
R104 (Sidetone 4)  
4-6 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Level and Frequency Response Check, Intercom Channel to Speaker  
1 Set all front panel buttons to off. Set all volume controls to minimum.  
2 Connect an 8 ohm load across the speaker output (J27, tip and ring)  
3 Connect an AC voltmeter and an oscilloscope across the speaker output.  
4 Connect the signal generator to intercom channel 1, and adjust the generator output to –1 dBu,  
1 kHz.  
5 Set the SPKR ON and CH 1 TALK buttons to on.  
6 Rotate the CH 1-3 volume control (R1), and check that the speaker output level reaches +18  
dBu (17.4 Vp-p) before clipping.  
7 Set the CH 1-3 volume control to get +15 dBu (4.4 VAC) at the speaker output. The volume  
control should be approximately at the 2 o’clock position.  
8 Activate speaker muting by grounding J22 pin 25 to pin 10. The speaker output level should  
drop to 5 mV or less, and the SPKR LED should turn off. Remove the ground connection.  
9 Activate speaker dim by grounding U15 pin 9.  
10Adjust R157 to the maximum clockwise position. The speaker output should be –5.5dB 1 dB  
below the level set in step 7.  
11Adjust R157 to the maximum counter-clockwise position. The speaker output should be –39.5  
dB 2 dB below the reference level set in step 7.  
12Reset R157 to the maximum clockwise position, and remove the speaker dim ground (U15 pin  
9).  
13Set the signal generator to –1 dBu, 100 Hz. The speaker output should be 10.8 dBu 2 dBu.  
14Set the signal generator to –1 dBu, 10 kHz. The speaker output should be 17.5 dBu 2 dBu.  
Level and Frequency Response, Program to Headphones and  
Speaker  
Program A to Left Headphone  
1 Set all front panel buttons to off. Set all volume controls to minimum.  
2 Set program jumpers J16, J17 and J18 to assign PROGRAM A and PROGRAM B inputs to the  
headphones and speaker (pins 1 & 2 shorted on all three jumpers).  
3 Remove the signal generator from channel 1, and reconnect it to the PROGRAM A input (J14  
tip and ring).  
4 Set the signal generator to 0 dBu, 1 kHz.  
5 Set the PGM VOL control to maximum.  
6 Measure the level at the left headphone output. It should be 1.3 dBu 2 dBu.  
7 Set the signal generator to 0 dBu, 100 Hz. The left headphone output should be 0.8 dBu 2  
dBu.  
8 Set the signal generator to 0 dBu, 10 kHz. The left headphone output should be –3.8 dBu 2  
dBu.  
9 Reset the generator to 0 dBu, 1 kHz.  
10Remove jumper J16 (program not assigned to left headphone). Verify that the signal level  
drops at least 35 dB from the reference level in step 9.  
4-7  
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11Restore jumper J16 to short pins 1 & 2.  
Program B to Right Headphone  
1 Remove the signal from the PROGRAM A input, and connect it to the PROGRAM B input.  
2 Measure the level at the right headphone output (J2, 3 & 5). It should be 1.3 dBu 2 dBu.  
(Program volume at maximum.)  
3 Set the signal generator to 0 dBu, 100 Hz. The right headphone output should be 0.8 dBu 2  
dBu.  
4 Set the signal generator to 0 dBu, 10 kHz. The right headphone output should be –3.8 dBu 2  
dBu.  
5 Reset the generator to 0 dBu, 1 kHz.  
6 Remove jumper J17 (program not assigned to right headphone). Verify that the signal level  
drops at least 35 dB from the reference level in step 2.  
7 Restore jumper J17 to short pins 1 & 2.  
Program to Speaker  
1 Connect the AC voltmeter across the 8 ohm load at the speaker output  
2 Set the SPKR ON button to the on position.  
3 Measure the level at he speaker output. It should be 6 dBu 2 dBu. (Program volume at  
maximum.)  
4 Set the signal generator to 0 dBu, 100 Hz. The speaker output should be 1.3 dBu 2 dBu.  
5 Set the signal generator to 0 dBu, 10 kHz. The speaker output should be 7.3 dBu 2 dBu.  
6 Reset the generator to 0 dBu, 1 kHz.  
7 Remove jumper J18 (program not assigned to speaker). Verify that the signal level drops at  
least 35 dB from the reference level in step 3.  
8 Restore jumper J18 to short pins 1 & 2.  
IFB Test  
IFB B  
1 Set all front panel buttons to off. Set all volume controls to minimum.  
2 Move the J5 jumper to short pins 1 and 2 (IFB B assigned to channel 4).  
3 Check the output level across intercom channel 4. It should be –9.8 dBu 2 dBu.  
4 Turn on the CH 4 TALK and MIC ON buttons. The channel 4 output should drop at least 45  
dB from the reference level in step 3.  
5 Turn off the CH 4 TALK and MIC ON buttons.  
6 Ground the Key 4 input (short J22 pin 20 to pin 10). The channel 4 output should drop at least  
45 dB from the reference level in step 3.  
7 Remove the Key 4 ground.  
8 Move the J5 jumper to short pins 2 and 3.  
4-8 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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IFB A  
1 Move the J4 jumper to short pins 1 and 2 (IFB A assigned to channel 3).  
2 Remove the signal from PROGRAM B input, and connect it to the PROGRAM A input. Set  
the signal generator to 0 dBu, 1 kHz.  
3 Check the output level across intercom channel 3. It should be –9.8 dBu 2 dBu.  
4 Turn on the CH 3 TALK and MIC ON buttons. The channel 3 output should drop at least 45  
dB from the reference level in step 3.  
5 Turn off the CH 3 TALK and MIC ON buttons.  
6 Ground the Key 3 input (short J22 pin 7 to pin 10). The channel 3 output should drop at least  
45 dB from the reference level in step 3.  
7 Remove the Key 3 ground.  
8 Move the J4 jumper to short pins 2 and 3.  
Level and Frequency Response Check, Four-Wire Input to  
Headphone  
Four-Wire A Input to Left Headphone  
1 Set all front panel buttons to off. Set all volume controls to minimum.  
2 Remove the signal generator from the Program A input, and connect it to the Four-Wire A  
input (AUXILIARY connector J22, pins 8 and 21). Set the generator to 0 dBu, 1 kHz.  
3 Move jumper J19 to short pins 3 & 4 (Four-Wire A input always on).  
4 Set the CH 1-3 volume control to measure 0 dBu at the left headphone output. (The control  
should be at about the 2 o’clock position.)  
5 Set the signal generator to 0 dBu, 100 Hz. The left headphone output should be –0.9 dBu 2  
dBu.  
6 Set the signal generator to 0 dBu, 10 kHz. The left headphone output should be –4.7 dBu 2  
dBu.  
7 Move jumper J19 to short pins 2 & 3 (Four-Wire A input off).  
Four-Wire B input to Right Headphone  
1 Remove the signal from the Four-Wire A input, and connect it to the Four-Wire B input (J22,  
pins 9 & 22).  
2 Move jumper J20 to short pins 3 & 4 (Four-Wire B input always on).  
3 Set the CH 2-4 volume control to measure 0 dBu at the right headphone output. (The control  
should be at about the 2 o’clock position.)  
4 Set the signal generator to 0 dBu, 100 Hz. The right headphone output should be –0.9 dBu 2  
dBu.  
5 Set the signal generator to 0 dBu, 10 kHz. The right headphone output should be –4.7 dBu 2  
dBu.  
6 Move jumper J20 to short pins 2 &3 (Four-Wire B input off).  
4-9  
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Panel Mic to Channel Test  
1 Turn all front panel buttons off. Set all volume controls to minimum.  
2 Remove the signal from the Four-Wire B input and reconnect it to the panel mic input (J28 tip  
and ring, it is easiest to connect to the back of the connector.).  
3 Set the signal generator to –25 dBu, 1 kHz.  
4 Turn on the CH 1 TALK, MIC ON and PANEL MIC buttons.  
5 Check the channel 1 output. It should be –0.9 dBu 2 dBu.  
Carbon Mic to Channel Test  
1 Turn off the PANEL MIC and MIC ON buttons. (Only the CH 1 TALK LED should be on.)  
2 Connect a 470 ohm resistor across the CARBON MIC HEADSET jack (J3 tip and ring). The  
MIC ON LED should turn on.  
3 Remove the signal from the panel mic input, and reconnect it to the CARBON MIC  
HEADSET jack.  
4 Set the signal generator to 11.2 dBu, 1 kHz.  
5 Check the channel 1 output. It should be –0.9 dBu 2 dBu.  
6 Remove the 470 ohm resistor from the carbon mic input.  
VOX Test  
1 Remove the signal from the CARBON MIC HEADSET jack, and reconnect it to the DYN  
MIC HEADSET jack mic input (J2 pins 1 & 2).  
2 Set the generator to –45 dBu, 1 kHz.  
3 Set DIP switch DS8 to the on position (VOX enabled), and note that the MIC ON LED turns  
on.  
4 Adjust the signal generator output level to zero, and note that the MIC ON LED turns off.  
5 Reset DS8 to off.  
Mic Kill Receive Test  
1 Set all buttons to off.  
2 Remove the signal from the DYN MIC HEADSET jack mic input, and reconnect it to intercom  
channel 1.  
3 Adjust signal generator to –5 dBu, 24 kHz (check frequency with frequency counter).  
4 Set the MIC ON button to on.  
5 Activate the CH 1 TALK button. The MIC ON LED should turn off.  
6 Attenuate the signal input by 20 dB. Try turning on the MIC ON button. It should not turn on.  
7 Attenuate the signal an additional 10 dB. Try turning on the MIC ON button. It should turn on.  
8 Adjust signal generator to –5 dBu at 22.320 kHz.  
9 Try turning the MIC ON button on and off. It should turn on and off as usual.  
10Adjust the signal generator to –5 dBu at 23.520 kHz.  
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11Try turning the MIC ON button on. It should not stay on.  
12Adjust signal generator to –5 dBu at 25.680 kHz.  
13Try turning the MIC ON button on and off. It should turn on and off as usual.  
14Adjust signal generator to –5 dBu at 24.480 kHz.  
15Try turning the MIC ON button on. It should not stay on.  
16Remove the signal generator from channel 1.  
Mic Kill Transmit Test  
1 Set all front panel buttons to off.  
2 Connect a frequency counter an AC meter to the intercom channel 1 output.  
3 Transmit a mic kill signal on intercom channel 1 (tap the CALL button 3 times, then press and  
hold the CH 1 TALK key).  
4 Check that the signal on the channel 1 output is between 23.7 to 23.9 kHz at –9.8 dBu 2 dBu.  
5 Release the CH 1 TALK button.  
Call Transmit Test  
1 Set all front panel buttons to off.  
2 Transmit a call signal on intercom channel 1 (tap the CALL button, and while the call LED is  
flashing, press and hold the CH 1 TALK key).  
3 Check that the signal on the channel 1 output is between 19.9 to 20.1 kHz at –9.8 dBu 2 dBu.  
4 Release the CH 1 TALK button.  
Call Receive Test  
1 Set all buttons to off.  
2 Reconnect the signal generator to intercom channel 1.  
3 Adjust signal generator to –5 dBu, 20 kHz (check frequency with frequency counter).  
4 Check that the CALL and CH 1 TALK LED’s are flashing.  
5 Attenuate the signal input by 20 dB, and check that the LED’s are still flashing.  
6 Attenuate the signal an additional 10 dB. The LED’s should stop flashing.  
7 Adjust signal generator to –5 dBu, 18.600 kHz.  
8 Verify that the LED’s do not flash.  
9 Adjust signal generator to –5 dBu, 21.400 kHz.  
10Verify that the LED’s do not flash.  
11Adjust signal generator to –5 dBu, 19.600 kHz.  
12Verify that the LED’s do flash.  
13Adjust signal generator to –5 dBu, 20.400 kHz.  
14Verify that the LED’s do flash.  
15Remove the signal generator and frequency counter.  
4-11  
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ISO Test  
1 Set DIP switch DS3 to off (two-channel, two-wire mode).  
2 Set DIP switch DS5 to on (talk muted during ISO).  
3 Set all TALK and LISTEN buttons to on.  
4 Connect a 100 ohm resistor from the ISO input (J22 pin 12) to circuit common (J22 pin 10).  
Observe that the MIC ON LED turns on and the channel 1 and 2 TALK buttons turn off.  
5 Remove the 100 ohm resistor across the ISO input.  
6 Reset DIP switch DS3 to on and DS5 to off.  
Remote Mic Switch Test  
1 Set all buttons to off.  
2 Connect a 100 ohm resistor from the remote mic switch input (J22 pin 25) to circuit common  
(J22 pin 10), and observe that the MIC ON LED turns on.  
3 Remove the 100 ohm resistor.  
Program Lockout Test  
1 Set DIP switch DS4 to on (front panel setup lockout enabled).  
2 Press and hold the CALL button for ten seconds, and verify that the MCE325 does not enter  
program mode.  
3 Reset DS4 to off.  
Noise Checks  
1 Connect a 150 ohm load across the dynamic mic input (J2 pins 1 and 2).  
2 Connect an 8 ohm load across the speaker output.  
3 Connect 51 ohm loads across the left headphone output (J2 pins 3 & 4) and right headphone  
output (J2 pins 3 &5).  
4 Terminate each intercom channel into 200 ohms.  
5 Set the MIC ON button to on.  
6 Set the SPKR ON button to on.  
7 Set all other front panel buttons to off.  
8 Set all volume controls to minimum.  
Note: Noise measurements in the following steps were made using a 30 kHz low pass filter  
with +20 dB of gain inserted between the AC voltmeter and the MCE325.  
9 Set the CH 1-3 volume control to maximum. Measure noise across the left headphone output. It  
should measure -44 dBu or less.  
10Set the CH 1-3 volume control to minimum and set the CH 2-4 volume control to maximum.  
Measure noise across the right headphone output. It should measure –44 dBu or less.  
11Set the CH 2-4 volume control to minimum. Measure noise across the speaker output. The  
meter should read –44 dBu or less.  
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12Turn on the SPKR ON button. The meter should read –38 dBu or less. Turn off the SPKR ON  
button.  
NOTE  
Noise measurements in the following steps were made using a 400 Hz to 30 kHz bandpass  
filter with +40 dB of gain.  
13Turn on the MIC ON switch. Measure noise at U1 pin 1 (mic preamp out). The voltmeter  
should read –26 dBu or less.  
14Turn on the PANEL MIC button. The meter should read –37 dBu or less.  
15Turn all buttons off.  
16Measure noise at U12 pin 7 (program A preamp out). The voltmeter should read –51 dBu or  
less.  
17Measure noise at U12 pin 1 (program B preamp out). The voltmeter should read –51 dBu or  
less.  
18Measure noise across intercom channels 1 through 4. All should measure –50 dBu or less.  
4-13  
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S E C T I O N  
C
HAPTER5  
PARTS LISTS  
Packaging Assembly (9000-6464-00)  
Table 5.1 Reference PD6464 Drawing, Section 6  
Item No.  
Description  
User Manual, MCE325 User Station  
Label, Warning  
RTS Part No.  
9350-6464-00  
9170-6739-00  
9010-6464-00  
9020-6793-00  
2705-0020-00  
9150-6643-09  
9150-6643-10  
9150-6643-11  
9150-6643-12  
9150-6643-13  
9150-6643-14  
9150-6643-15  
9150-6643-16  
9150-6643-10  
4501-0064-00  
1
2
3
4
5
Final Assy, MCE325  
Assy, 200-ohm Termination Plug  
Keycap, Blank  
Keycap, Printed (TALK 3)  
Keycap, Printed (TALK 4)  
Keycap, Printed (IFB 1)  
Keycap, Printed (IFB 2)  
Keycap, Printed (LISTEN 3)  
Keycap, Printed (LISTEN 4)  
Keycap, Printed (SSA 1)  
Keycap, Printed (SSA 2)  
Keycap, Printed (PAGE)  
Keycap, Stem  
6
Final Assembly, MCE325 (9010-6464-00)  
Table 5.2 Reference AS6464 Drawing, Section 6  
Item No.  
Description  
RTS Part No.  
1
2
3
4
5
6
7
8
9
Front Panel Assy, MCE325  
Back Panel Assy, MCE325  
Case, MCE/MCS  
9020-6261-00  
9020-6262-00  
9060-6260-00  
9160-6305-00  
1008-4081-00  
N/A  
MCE/MCS Case Screw  
Screw, #4-40 x 1/4  
Valox Film, 0.010” Thick  
Rubber Stick-on Button  
4501-5012-00  
Label, Programming and FCC Notice 9170-6776-00  
Lug, Solder, #16 1003-0003-00  
5-1  
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Front Panel Assembly (9020-6261-00)  
Table 5.3 Reference AS6261 Drawing, Section 6  
Item No. Description  
RTS Part No.  
1
Bezel, MCE325  
9070-6261-00  
2
PC Board Assy, Front Panel, MCE325 9030-6246-00  
3
Bushing Adapter  
9110-6273-00  
4501-0064-00  
2703-0033-00  
2703-0034-00  
4501-0061-00  
2018-0077-00  
4501-0063-00  
4501-0062-00  
51856-003  
5
Keycap Stem  
6
Knob, Channel Volume, MCE325  
Knob, Program Volume, MCE325  
Lightpipe, Button Indicator  
Connector Insert, 6-pin Female (J2)  
Plug, Panel Microphone  
Lightpipe, Call Indicator  
Screw, Thread Forming  
7
8
9
10  
11  
12  
13  
14  
15  
16  
17  
20  
21  
22  
23  
24  
25  
26  
27  
Connector Housing, 3-pin (P1)  
59958-003  
Phone Jack with Metal Bushing (J28) 2013-0048-00  
Connector Housing, 6-pin (P2)  
Contact, Housing  
59958-006  
59958-200  
Flex Cable, 0.050” Centers  
Keycap, Printed (TALK 1)  
Keycap, Printed (LISTEN 1)  
Keycap, Printed (TALK 2)  
Keycap, Printed (LISTEN 2)  
Keycap, Printed (CALL)  
Keycap, Printed (PANEL MIC)  
Keycap, Printed (SPKR ON)  
Keycap, Printed (MIC ON)  
2515-0013-00  
9150-6643-01  
9150-6643-02  
9150-6643-03  
9150-6643-04  
9150-6643-05  
9150-6643-06  
9150-6643-07  
9150-6643-08  
5-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Back Panel Assembly (9020-6262-00)  
Table 5.4 Reference AS6262 Drawing, Section 6  
Item No.  
Description  
PC Board Assy, Main  
RTS Part No.  
1
2
9030-6245-00  
9020-6324-00  
9080-6262-00  
Heatsink Assy  
Panel, Rear  
3
4
Jack, Phone, 3 conductor, double closed circuit (J27) 2013-0003-00  
5
Connector Housing (P23)  
cord, AC Power, Gray  
Strain Relief, Flexible  
Fuse, 0.5A, 250V Slo-blo  
Fuse Cap  
57767-203  
6
2504-0004-00  
2509-0025-00  
50547-015  
7
8
9
57074-006  
10  
11  
12  
13  
15  
16  
17  
Fuse Holder body w/mtg Nut  
Terminal, Wire Joint, Nylong  
Screw, #4-40 x ¼  
2802-0003-00  
2017-0013-00  
1008-4023-00  
1007-0001-00  
1007-0002-00  
51378-002  
Nut, Hex Kep, #4-40  
Nut, Hex Kep, #4-40  
Lug, Solder, #16  
Shrink Tubing  
LP  
Heatsink Assembly (9020-6324-00)  
Table 5.5 Reference 9020-6324-00 Drawing, Section 6  
Item No.  
Description  
RTS Part No.  
1
2
3
4
5
6
7
8
9
Heatsink, Model MCE325  
IC LM4752T  
9180-6324-01  
511386000S  
Adj. Regulatro, 3 Terminal, LM317T 53290000  
Insulator  
57896000  
1006004000  
50013035  
1006004100  
51845040  
51741000  
Washer, Nylon Shoulder  
Washer  
Washer, Compression  
Screw PH, Cross  
Thermal Compound  
Main PC Board Assembly (9030-6245-01)  
Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
Ref No.  
Description  
Capacitor, EL, 100µF, 25V  
RTS Part No.  
C1  
51821524  
52676113  
1514R1022L  
52676113  
52676113  
51821110  
C10 Capacitor, CM, 0.1µF, 50V  
C100 Capacitor, Mylar, 1nF, 100V  
C101 Capacitor, CM, 0.1µF, 50V  
C102 Capacitor, CM, 0.1µF, 50V  
C103 Capacitor, EL, 10µF, 50V  
5-3  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
C104 Capacitor, CM, 0.1µF, 50V  
C105 Capacitor, EL, 100µF, 25V  
C106 Capacitor, EL, 4.7µf, 25V  
C107 Capacitor, EL, 4.7µf, 25V  
C108 Capacitor, EL, 100µF, 25V  
C109 Capacitor, EL, 1000µF, 25V  
C11 Capacitor, CM, 0.1µF, 50V  
C110 Capacitor, CM, 0.1µF, 50V  
C111 Capacitor, CM, 0.1µF, 50V  
C112 Capacitor, EL, 220µF, 50V  
C113 Capacitor, EL, 220µF, 50V  
C115 Capacitor, CD, 10pF, 500V  
C116 Capacitor, CD, 10pF, 500V  
C117 Capacitor, CD, 10pF, 500V  
C118 Capacitor, CM, 0.1µF, 50V  
C119 Capacitor, Mylar, 0.01µF, 50V  
C12 Capacitor, EL, 10µF, 50V  
C120 Capacitor, CD, 100pF, 100V  
C121 Capacitor, CD, 10pF, 500V  
C122 Capacitor, CM, 0.1µF, 50V  
C125 Capacitor, EL, 4700µF, 35V  
C126 Capacitor, CD, 0.1µF, 500V  
C127 Capacitor, EL, 10µF, 50V  
C128 Capacitor, EL, 10µF, 50V  
C129 Capacitor, EL, 100µF, 25V  
C13 Capacitor, CM, 0.1µF, 50V  
C130 Capacitor, CM, 0.1µF, 50V  
C131 Capacitor, EL, 10µF, 50V  
C132 Capacitor, CM, 0.1µF, 50V  
C133 Capacitor, EL, 100µF, 25V  
C134 Capacitor, CM, 0.1µF, 50V  
C135 Capacitor, EL, 22µF, 50V  
C136 Capacitor, CM, 0.1µF, 50V  
C137 Capacitor, CM, 0.1µF, 50V  
C138 Capacitor, CM, 0.1µF, 50V  
C139 Capacitor, CM, 0.1µF, 50V  
C14 Capacitor, EL, 100µF, 25V  
C140 Capacitor, CM, 0.1µF, 50V  
C141 Capacitor, CM, 0.1µF, 50V  
C142 Capacitor, EL, 4.7µf, 25V  
C143 Capacitor, EL, 4.7µf, 25V  
C15 Capacitor, Mylar, 150pF, 100V  
C16 Capacitor, CM, 0.1µF, 50V  
C17 Capacitor, EL, 1µF, 50V  
C18 Capacitor, CD, 100pF, 100V  
C19 Capacitor, CD, 100pF, 100V  
52676113  
51821524  
51821621  
51821622  
51821524  
51821526  
52676113  
52676113  
52676113  
52157534  
52157534  
52157502  
52157502  
52157502  
52676113  
52719007  
51821110  
1501R1011L  
52157502  
52676113  
1513R4784G  
1510R1042Q  
51821110  
51821110  
51821524  
52676113  
52676113  
51821110  
52676113  
51821524  
52676113  
51821640  
52676113  
52676113  
52676113  
52676113  
51821524  
52676113  
52676113  
51821623  
51821624  
52157332  
52676113  
51821106  
1501R1011L  
1501R1011L  
5-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
C2 Capacitor, EL, 10µF, 50V  
51821110  
1501R1011L  
1501R1011L  
52676113  
C20 Capacitor, CD, 100pF, 100V  
C21 Capacitor, CD, 100pF, 100V  
C22 Capacitor, CM, 0.1µF, 50V  
C23 Capacitor, CD, 10pF, 500V  
C24 Capacitor, CM, 0.1µF, 50V  
C25 Capacitor, EL, 22µF, 50V  
C26 Capacitor, EL, 47µF, 16V  
C27 Capacitor, EL, 22µF, 50V  
C28 Capacitor, CD, 100pF, 100V  
C29 Capacitor, CD, 100pF, 100V  
52157502  
52676113  
51821640  
51821068  
51821640  
1501R1011L  
1501R1011L  
51821524  
C3  
Capacitor, EL, 100µF, 25V  
C30 Capacitor, CD, 100pF, 100V  
C31 Capacitor, CD, 100pF, 100V  
C32 Capacitor, CM, 0.1µF, 50V  
C33 Capacitor, CD, 10pF, 500V  
C34 Capacitor, EL, 47µF, 16V  
C35 Capacitor, EL, 22µF, 50V  
C36 Capacitor, EL, 22µF, 50V  
C37 Capacitor, CD, 100pF, 100V  
C38 Capacitor, CD, 100pF, 100V  
C39 Capacitor, CD, 100pF, 100V  
1501R1011L  
1501R1011L  
52676113  
52157502  
51821068  
51821640  
51821640  
1501R1011L  
1501R1011L  
1501R1011L  
52676101  
C4  
Capacitor, CM, 1nF, 50V  
C40 Capacitor, CD, 100pF, 100V  
C41 Capacitor, CM, 0.1µF, 50V  
C42 Capacitor, CD, 10pF, 500V  
C43 Capacitor, CM, 0.1µF, 50V  
C44 Capacitor, EL, 22µF, 50V  
C45 Capacitor, EL, 47µF, 16V  
C46 Capacitor, EL, 22µF, 50V  
C47 Capacitor, CD, 100pF, 100V  
C48 Capacitor, CD, 100pF, 100V  
C49 Capacitor, CD, 100pF, 100V  
1501R1011L  
52676113  
52157502  
52676113  
51821640  
51821068  
51821640  
1501R1011L  
1501R1011L  
1501R1011L  
51821524  
C5  
Capacitor, EL, 100µF, 25V  
C50 Capacitor, CD, 100pF, 100V  
C51 Capacitor, CM, 0.1µF, 50V  
C52 Capacitor, CD, 10pF, 500V  
C53 Capacitor, EL, 22µF, 50V  
C54 Capacitor, EL, 47µF, 16V  
C55 Capacitor, EL, 22µF, 50V  
C56 Capacitor, CM, 0.1µF, 50V  
C57 Capacitor, EL, 22µF, 50V  
C58 Capacitor, CM, 0.1µF, 50V  
C59 Capacitor, CD, 100pF, 100V  
1501R1011L  
52676113  
52157502  
51821640  
51821068  
51821640  
52676113  
51821640  
52676113  
1501R1011L  
52676101  
C6  
Capacitor, CM, 1nF, 50V  
C60 Capacitor, EL, 10µF, 50V  
51821110  
5-5  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
C61 Capacitor, Mylar, 1nF, 100V  
C62 Capacitor, EL, 10µF, 50V  
C63 Capacitor, CD, 100pF, 100V  
C64 Capacitor, Mylar, 1nF, 100V  
C65 Capacitor, CM, 0.1µF, 50V  
C66 Capacitor, EL, 10µF, 50V  
C67 Capacitor, Mylar, 1nF, 100V  
C68 Capacitor, EL, 10µF, 50V  
C69 Capacitor, CD, 100pF, 100V  
1514R1022L  
51821110  
1501R1011L  
1514R1022L  
52676113  
51821110  
1514R1022L  
51821110  
1501R1011L  
52676101  
C7  
Capacitor, CM, 1nF, 50V  
C70 Capacitor, Mylar, 1nF, 100V  
C71 Capacitor, EL, 10µF, 50V  
C72 Capacitor, Mylar, 1nF, 100V  
C73 Capacitor, EL, 10µF, 50V  
C74 Capacitor, CD, 100pF, 100V  
C75 Capacitor, Mylar, 1nF, 100V  
C76 Capacitor, CM, 0.1µF, 50V  
C77 Capacitor, EL, 10µF, 50V  
C78 Capacitor, EL, 10µF, 50V  
C79 Capacitor, CD, 100pF, 100V  
1514R1022L  
51821110  
1514R1022L  
51821110  
1501R1011L  
1514R1022L  
52676113  
51821110  
51821110  
1501R1011L  
52676113  
C8  
Capacitor, CM, 0.1µF, 50V  
C80 Capacitor, Mylar, 1nF, 100V  
C81 Capacitor, Mylar, 1nF, 100V  
C82 Capacitor, EL, 1µF, 50V  
C83 Capacitor, EL, 10µF, 50V  
C84 Capacitor, CD, 100pF, 100V  
C84 500PF  
1514R1022L  
1514R1022L  
51821106  
51821110  
1501R1011L  
52157018  
C85 Capacitor, CM, 0.1µF, 50V  
C86 Capacitor, EL, 10µF, 50V  
C87 Capacitor, EL, 10µF, 50V  
C88 Capacitor, CM, 0.1µF, 50V  
C89 Capacitor, EL, 10µF, 50V  
52676113  
51821110  
51821110  
52676113  
51821110  
C9  
Capacitor, CM, 0.1µF, 50V  
52676113  
C90 Capacitor, EL, 10µF, 50V  
C91 Capacitor, CM, 0.1µF, 50V  
C92 Capacitor, Mylar, 1nF, 100V  
C93 Capacitor, CM, 0.1µF, 50V  
C94 Capacitor, CM, 0.1µF, 50V  
C95 Capacitor, EL, 10µF, 50V  
C96 Capacitor, CM, 0.1µF, 50V  
C97 Capacitor, EL, 100µF, 25V  
C98 Capacitor, CM, 0.1µF, 50V  
C99 Capacitor, CM, 0.1µF, 50V  
CR1 Bridge Rectifier, 4A, 50VRMS  
51821110  
52676113  
1514R1022L  
52676113  
52676113  
51821110  
52676113  
51821524  
52676113  
52676113  
1601097000  
50745005T  
50745005T  
D1  
Diode, 1N4004  
D10 Diode, 1N4004  
5-6 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
D11 Diode, 1N4004  
D12 Diode, 1N4004  
D13 Diode, 1N4004  
D14 Diode, 1N914B  
D15 Diode, 1N914B  
D16 Diode, 1N914B  
50745005T  
50745005T  
50745005T  
160109140B  
160109140B  
160109140B  
160109140B  
50745005T  
50745005T  
50745005T  
160109140B  
160109140B  
160109140B  
50745005T  
50745005T  
50745005T  
50745005T  
2404000100  
2404000100  
2404000100  
2404000100  
59958103  
D2  
Diode, 1N914B  
D20 Diode, 1N4004  
D21 Diode, 1N4004  
D22 Diode, 1N4004  
D3  
D4  
D5  
D6  
D7  
D8  
D9  
Diode, 1N914B  
Diode, 1N914B  
Diode, 1N914B  
Diode, 1N4004  
Diode, 1N4004  
Diode, 1N4004  
Diode, 1N4004  
FB1 #73 SHIELD BEAD  
FB2 #73 SHIELD BEAD  
FB3 #73 SHIELD BEAD  
FB4 #73 SHIELD BEAD  
J1  
J10  
J14  
J15  
J16  
J17  
J18  
J19  
J2  
Connector, 3-pin  
Connector, Audio  
Jack, PC Mt., 3/8  
Jack, PC Mt., 3/8  
Header, 3-pin  
59893001  
2013004900  
2013004900  
2007009900  
2007009900  
2007009900  
2007013400  
59958106  
Header, 3-pin  
Header, 3-pin  
Header, 4-pin  
Connector, 6-pin  
Header, 4-pin  
J20  
J21  
J22  
J23  
J24  
J3  
2007013400  
2006009600  
2004004000  
2007011800  
2007009900  
2013004900  
2007009900  
2007009900  
2007009900  
2007009900  
59893001  
Connector  
Connector, D-Sub, 25-pin  
Header, 3-pin  
Header, 3-pin  
Jack, PC Mt., 3/8  
Header, 3-pin  
J4  
J5  
Header, 3-pin  
J6  
Header, 3-pin  
J7  
Header, 3-pin  
J8  
Connector, Audio  
Connector, Audio  
Transistor, 2N5087  
J9  
59892001  
Q1  
1602508700  
1602546000  
1602521000  
1602548400  
Q10 Transistor, 2N5460  
Q2  
Q3  
Transistor, 2N5210  
Transistor, 2N5484  
5-7  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
Q4  
Q5  
R1  
Transistor, 2N5210  
1602521000  
1602521000  
52154060  
54034301  
524154028  
52154036  
1409006000  
54035604  
54035200  
54035604  
54035200  
52154084  
52154065  
52154012  
54035200  
54035100  
54035200  
52154060  
54035100  
54035200  
54035100  
54035200  
54035100  
524154028  
54035200  
54035100  
54035200  
54035100  
52154036  
54035200  
54035100  
524154028  
54035200  
54035100  
52154036  
524154028  
52154077  
52154004  
52154007  
52154020  
52154020  
52154012  
54035200  
57148407  
524154028  
52154305  
Transistor, 2N5210  
Resistor, CF, 1K Ohm, 5%, 1/8W  
R10 Resistor, MF, 3.01K Ohm, 1%, 1/8W  
R100 Resistor, CF, 22K Ohm, 5%, 1/8W  
R101 Resistor, CF, 10K Ohm, 5%, 1/8W  
R104 Trimpot, 10K Ohm, Linear  
R105 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R106 Resistor, MF, 20K Ohm, 1%, 1/8W  
R107 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R108 Resistor, MF, 20K Ohm, 1%, 1/8W  
R109 Resistor, CF, 100 Ohm, 5%, 1/8W  
R11 Resistor, CF, 620 Ohm, 5%, 1/8W  
R110 Resistor, CF, 100K Ohm, 5% 1/8W  
R117 Resistor, MF, 20K Ohm, 1%, 1/8W  
R118 Resistor, MF, 10K Ohm, 1%, 1/8W  
R119 Resistor, MF, 20K Ohm, 1%, 1/8W  
R12  
Resistor, CF, 1K Ohm, 5%, 1/8W  
R120 Resistor, MF, 10K Ohm, 1%, 1/8W  
R124 Resistor, MF, 20K Ohm, 1%, 1/8W  
R125 Resistor, MF, 10K Ohm, 1%, 1/8W  
R126 Resistor, MF, 20K Ohm, 1%, 1/8W  
R127 Resistor, MF, 10K Ohm, 1%, 1/8W  
R13 Resistor, CF, 22K Ohm, 5%, 1/8W  
R130 Resistor, MF, 20K Ohm, 1%, 1/8W  
R131 Resistor, MF, 10K Ohm, 1%, 1/8W  
R132 Resistor, MF, 20K Ohm, 1%, 1/8W  
R133 Resistor, MF, 10K Ohm, 1%, 1/8W  
R135 Resistor, CF, 10K Ohm, 5%, 1/8W  
R138 Resistor, MF, 20K Ohm, 1%, 1/8W  
R139 Resistor, MF, 10K Ohm, 1%, 1/8W  
R14 Resistor, CF, 22K Ohm, 5%, 1/8W  
R140 Resistor, MF, 20K Ohm, 1%, 1/8W  
R141 Resistor, MF, 10K Ohm, 1%, 1/8W  
R142 Resistor, CF, 10K Ohm, 5%, 1/8W  
R15 Resistor, CF, 22K Ohm, 5%, 1/8W  
R152 Resistor, CF, 200 Ohm, 5%, 1/8W  
R153 Resistor, CF, 220K Ohm, 5%, 1/8W  
R153 160K  
R154 Resistor, CF, 47K Ohm, 5%, 1/8W  
R155 Resistor, CF, 47K Ohm, 5%, 1/8W  
R156 Resistor, CF, 100K Ohm, 5% 1/8W  
R156 Resistor, MF, 20K Ohm, 1%, 1/8W  
R157 Trimpot, 20K Ohm, Linear  
R16 Resistor, CF, 22K Ohm, 5%, 1/8W  
R17 Resistor, CF, 100 Ohm, 5%, 1/4W  
5-8 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
R170 Resistor, CF, 10K Ohm, 5%, 1/8W  
R171 Resistor, CF, 10K Ohm, 5%, 1/8W  
R172 Resistor, MF, 201 Ohm, 1%, 1/8W  
R173 Resistor, CF, 100K Ohm, 5% 1/8W  
R174 Resistor, MF, 201 Ohm, 1%, 1/8W  
R175 Resistor, CF, 100K Ohm, 5% 1/8W  
R176 Resistor, CF, 22K Ohm, 5%, 1/8W  
R177 Resistor, CF, 100K Ohm, 5% 1/8W  
R178 Resistor, CF, 1M Ohm, 5%, 1/8W  
R18 Resistor, CF, 100 Ohm, 5%, 1/4W  
R180 Resistor, CF, 1K Ohm, 5%, 1/8W  
R181 Resistor, CF, 2.7 Ohm, 5%, 1/8W  
R182 Resistor, CF, 22K Ohm, 5%, 1/8W  
R183 Resistor, CF, 10 Ohm, 5%, 1/8W  
R184 Resistor, CF, 22K Ohm, 5%, 1/8W  
R185 Resistor, CF, 100K Ohm, 5% 1/8W  
R186 Resistor, CF, 1K Ohm, 5%, 1/8W  
R187 Resistor, CF, 2.7 Ohm, 5%, 1/8W  
R188 Resistor, CF, 22K Ohm, 5%, 1/8W  
R189 Resistor, CF, 10 Ohm, 5%, 1/8W  
R19 Resistor, CF, 620 Ohm, 5%, 1/8W  
R198 Resistor, CF, 270K Ohm, 5%, 1/8W  
R199 Resistor, CF, 10K Ohm, 5%, 1/8W  
52154036  
52154036  
54032301  
52154012  
54032301  
52154012  
524154028  
52154012  
52154988  
52154305  
52154060  
52154122  
524154028  
52154108  
524154028  
52154012  
52154060  
52154122  
524154028  
52154108  
52154065  
52154002  
52154036  
52154053  
52154012  
52154980  
54034301  
52154012  
52154036  
52154060  
52154020  
524154028  
52154002  
52154002  
52154036  
52154012  
524154028  
524154028  
52154012  
52154698  
524154028  
54034301  
54032301  
52154004  
52154004  
54032909  
R2  
Resistor, Cf, 2K Ohm, 5%, 1/8W  
R20 Resistor, CF, 100K Ohm, 5% 1/8W  
R200 Resistor, CF, 2.2M Ohm, 5%, 1/8W  
R201 Resistor, MF, 3.01K Ohm, 1%, 1/8W  
R207 Resistor, CF, 100K Ohm, 5% 1/8W  
R208 Resistor, CF, 10K Ohm, 5%, 1/8W  
R209 Resistor, CF, 1K Ohm, 5%, 1/8W  
R21 Resistor, CF, 47K Ohm, 5%, 1/8W  
R211 Resistor, CF, 22K Ohm, 5%, 1/8W  
R212 Resistor, CF, 270K Ohm, 5%, 1/8W  
R213 Resistor, CF, 270K Ohm, 5%, 1/8W  
R214 Resistor, CF, 10K Ohm, 5%, 1/8W  
R215 Resistor, CF, 100K Ohm, 5% 1/8W  
R22 Resistor, CF, 22K Ohm, 5%, 1/8W  
R23 Resistor, CF, 22K Ohm, 5%, 1/8W  
R24 Resistor, CF, 100K Ohm, 5% 1/8W  
R26 Resistor, CF, 5.1M Ohm, 5%, 1/8W  
R261 Resistor, CF, 22K Ohm, 5%, 1/8W  
R262 Resistor, MF, 3.01K Ohm, 1%, 1/8W  
R263 Resistor, MF, 201 Ohm, 1%, 1/8W  
R264 Resistor, CF, 220K Ohm, 5%, 1/8W  
R265 Resistor, CF, 220K Ohm, 5%, 1/8W  
R266 Resistor, MF, 909 Ohm, 1%, 1/8W  
5-9  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
R267 Resistor, MF, 201 Ohm, 1%, 1/8W  
R268 Resistor, CF, 200 Ohm, 5%, 1/8W  
R269 Resistor, CF, 10K Ohm, 5%, 1/8W  
R27 Resistor, CF, 200 Ohm, 5%, 1/8W  
R28 Resistor, CF, 22K Ohm, 5%, 1/8W  
R29 Resistor, CF, 5.1M Ohm, 5%, 1/8W  
54032301  
52154077  
52154036  
52154077  
52154010  
52154698  
52154084  
52154012  
52154698  
52154012  
52154032  
524154028  
52154012  
52154036  
57148406  
52154084  
52154053  
52154012  
52154025  
52154996  
52154012  
54035200  
52154122  
52154122  
54035200  
54035200  
52154036  
524154028  
52154012  
52154036  
524154028  
52154020  
524154028  
54035200  
524154028  
1409006000  
54035604  
54035200  
52154060  
52154012  
54035604  
54035200  
52154084  
52154012  
524154028  
52154020  
R3  
Resistor, CF, 100 Ohm, 5%, 1/8W  
R30 Resistor, CF, 100K Ohm, 5% 1/8W  
R31 Resistor, CF, 5.1M Ohm, 5%, 1/8W  
R32 Resistor, CF, 100K Ohm, 5% 1/8W  
R33 Resistor, CF, 15K Ohm, 5%, 1/8W  
R34 Resistor, CF, 22K Ohm, 5%, 1/8W  
R35 Resistor, CF, 100K Ohm, 5% 1/8W  
R36 Resistor, CF, 10K Ohm, 5%, 1/8W  
R37 Trimpot, 10K Ohm, w/knob  
R38 Resistor, CF, 100 Ohm, 5%, 1/8W  
R39 Resistor, Cf, 2K Ohm, 5%, 1/8W  
R4  
Resistor, CF, 100K Ohm, 5% 1/8W  
R40 Resistor, CF, 30K Ohm, 5%, 1/8W  
R41 Resistor, CF, 470K Ohm, 5%, 1/8W  
R42 Resistor, CF, 100K Ohm, 5% 1/8W  
R43 Resistor, MF, 20K Ohm, 1%, 1/8W  
R44 Resistor, CF, 2.7 Ohm, 5%, 1/8W  
R45 Resistor, CF, 2.7 Ohm, 5%, 1/8W  
R46 Resistor, MF, 20K Ohm, 1%, 1/8W  
R47 Resistor, MF, 20K Ohm, 1%, 1/8W  
R48 Resistor, CF, 10K Ohm, 5%, 1/8W  
R49 Resistor, CF, 22K Ohm, 5%, 1/8W  
R5  
Resistor, CF, 100K Ohm, 5% 1/8W  
R50 Resistor, CF, 10K Ohm, 5%, 1/8W  
R51 Resistor, CF, 22K Ohm, 5%, 1/8W  
R52 Resistor, CF, 47K Ohm, 5%, 1/8W  
R53 Resistor, CF, 22K Ohm, 5%, 1/8W  
R54 Resistor, MF, 20K Ohm, 1%, 1/8W  
R55 Resistor, CF, 22K Ohm, 5%, 1/8W  
R57 Trimpot, 10K Ohm, Linear  
R58 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R59 Resistor, MF, 20K Ohm, 1%, 1/8W  
R6  
Resistor, CF, 1K Ohm, 5%, 1/8W  
R60 Resistor, CF, 100K Ohm, 5% 1/8W  
R61 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R62 Resistor, MF, 20K Ohm, 1%, 1/8W  
R63 Resistor, CF, 100 Ohm, 5%, 1/8W  
R64 Resistor, CF, 100K Ohm, 5% 1/8W  
R65 Resistor, CF, 22K Ohm, 5%, 1/8W  
R66 Resistor, CF, 47K Ohm, 5%, 1/8W  
5-10 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
R67 Resistor, CF, 22K Ohm, 5%, 1/8W  
R68 Resistor, CF, 22K Ohm, 5%, 1/8W  
R69 Resistor, CF, 22K Ohm, 5%, 1/8W  
524154028  
524154028  
524154028  
54034150  
52154036  
1409006000  
54035604  
54035200  
54035604  
54035200  
52154084  
52154012  
54034150  
524154028  
52154020  
524154028  
524154028  
524154028  
52154036  
1409006000  
54035604  
54034150  
54035200  
54035604  
54035200  
52154084  
52154012  
524154028  
52154020  
524154028  
524154028  
R7  
Resistor, MF, 301 Ohm, 1%, 1/8W  
R70 Resistor, CF, 10K Ohm, 5%, 1/8W  
R73 Trimpot, 10K Ohm, Linear  
R74 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R75 Resistor, MF, 20K Ohm, 1%, 1/8W  
R76 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R77 Resistor, MF, 20K Ohm, 1%, 1/8W  
R78 Resistor, CF, 100 Ohm, 5%, 1/8W  
R79 Resistor, CF, 100K Ohm, 5% 1/8W  
R8  
Resistor, MF, 301 Ohm, 1%, 1/8W  
R80 Resistor, CF, 22K Ohm, 5%, 1/8W  
R81 Resistor, CF, 47K Ohm, 5%, 1/8W  
R82 Resistor, CF, 22K Ohm, 5%, 1/8W  
R83 Resistor, CF, 22K Ohm, 5%, 1/8W  
R84 Resistor, CF, 22K Ohm, 5%, 1/8W  
R85 Resistor, CF, 10K Ohm, 5%, 1/8W  
R88 Trimpot, 10K Ohm, Linear  
R89 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R9  
Resistor, MF, 301 Ohm, 1%, 1/8W  
R90 Resistor, MF, 20K Ohm, 1%, 1/8W  
R91 Resistor, MF, 60.4K Ohm, 1%, 1/8W  
R92 Resistor, MF, 20K Ohm, 1%, 1/8W  
R94 Resistor, CF, 100 Ohm, 5%, 1/8W  
R95 Resistor, CF, 100K Ohm, 5% 1/8W  
R96 Resistor, CF, 22K Ohm, 5%, 1/8W  
R97 Resistor, CF, 47K Ohm, 5%, 1/8W  
R98 Resistor, CF, 22K Ohm, 5%, 1/8W  
R99 Resistor, CF, 22K Ohm, 5%, 1/8W  
RP1 Resistor Network, 100K Ohm X4, No Common, 1.1W 1411100302  
RP10 Resistor Network, 100K Ohm X4, No Common, 1.1W 1411100302  
RP11 Resistor Network, 100K Ohm X4, No Common, 1.1W 1411100302  
RP12 Resistor Network, 100K Ohm X4, No Common, 1.1W 1411100302  
RP14 Resistor Network, 680 Ohm X 5, No Common, 1.5W  
RP15 Resistor Network, 680 Ohm X 5, No Common, 1.5W  
1411680000  
1411680000  
RP2 Resistor Network, 22K Ohm X 9, Pin 1 Common, 1.5W 1411220201  
RP3 Resistor Network, 100K Ohm X4, No Common, 1.1W 1411100302  
RP5 Resistor Network, 22K Ohm X 9, Pin 1 Common, 1.5W 1411220201  
RP6 Resistor Network, 10K Ohm X 4, Pin 1 Common, 0.9W 1411100204  
RP7 Resistor Network, 10K Ohm X 4, Pin 1 Common, 0.9W 1411100204  
RP8 Resistor Network, 22K Ohm X 9, Pin 1 Common, 1.5W 1411220201  
RP9 Resistor Network, 22K Ohm X 9, Pin 1 Common, 1.5W 1411220201  
S1  
T1  
Switch, DIP, Low Profile  
R-Core XFMR  
1909000200  
9020653400  
5-11  
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Table 5.6 Reference 9027-6245-01 Drawing, Section 6  
U1 IC, Dual Low-noise Op-Amp, NE5532N  
53295000  
U10 IC, Dual Low-noise Op-Amp, NE5532N  
U11 IC, Dual Low-noise Op-Amp, TLO76  
U12 IC, Dual Low-noise Op-Amp, TLO77  
U13 IC, Analog Switch, CD4053BE  
U14 IC, Analog Switch, CD4053BE  
U15 IC, Analog Switch, CD4053BE  
U16 IC, Dual Low-noise Op-Amp, TLO78  
U17 IC, Dual Low-noise Op-Amp, NE5532N  
U18 IC, Audio Amp, LM386  
53295000  
1603013500  
1603013500  
46638P1  
46638P1  
46638P1  
1603013500  
53295000  
53281000  
U19 IC, Audio Amp, LM387  
53281000  
U2  
IC, Analog Switch, CD4053BE  
46638P1  
U20 IC, Reference, LM833  
1603083300  
46638P1  
U21 IC, Analog Switch, CD4053BE  
U22 IC, Undervoltage Sense, MC33064P-5  
U23 IC, UCN5821A  
1603013700  
160358210A  
160358210A  
160358210A  
53290000  
U24 IC, UCN5821A  
U25 IC, UCN5821A  
U27 IC, Voltage Regulator, LM317  
U28 IC, EEPROM, 1024 Bit, 93C56AN NA  
U29 Assy. Software, Version 1.6  
1603013800  
9020634816  
46638P1  
U3  
IC, Analog Switch, CD4053BE  
U30 IC, Quad 2-input NAND, 4093B  
160340930B  
46638P1  
U4  
U5  
U6  
U7  
U8  
U9  
IC, Analog Switch, CD4053BE  
IC, Dual Low-noise Op-Amp, TLO72  
IC, Dual Low-noise Op-Amp, TLO73  
IC, Dual Low-noise Op-Amp, TLO74  
IC, Dual Low-noise Op-Amp, TLO75  
IC, Dual Low-noise Op-Amp, NE5532N  
1603013500  
1603013500  
1603013500  
1603013500  
53295000  
XJ16 Jumper  
XJ17 Jumper  
XJ18 Jumper  
XJ19 Jumper  
XJ20 Jumper  
XJ24 Jumper  
XJ4 Jumper  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
2515001001  
53041002  
XJ5 Jumper  
XJ6 Jumper  
XJ7 Jumper  
XU1 IC Socket, 8-Pin  
XU29 IC Socket, 40-Pin  
53041308  
Y1  
Crystal, 4MHz, 20pF  
WASHER FLAT  
4-40X1/4  
3301000700  
52186006  
1008402300  
1008403500  
4-40X3/8  
5-12 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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PC Board Assembly, Front Panel (9030-6246-00)  
Table 5.7 Reference AS6246 Drawing, Section 6  
Ref No.  
Description  
RTS Part No.  
R1-R3 Pot, 10K Ohm, Audio  
DS9 LED, Super Bright, Red  
1406003901  
1801001900  
DS1-DS8 LED, Super Bright, Yellow 1801002200  
S1-S8 Keyswitch, No LED  
J1 Connector  
1911004300  
2006009600  
5-13  
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5-14 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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S E C T I O N  
C
HAPTER6  
DIAGRAMS  
6-1  
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6-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s  
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Date: 7/23/01  
Time : 05:20:45 PM  
DowTnloiatdlefro:mDWw:w\.TSoEmaMnuaPls.c\oAm.SAll6Ma2nu4al6s S_ea0rc1h ABnd.Dcoawnlload.  
Date: 7/23/01  
Time : 05:27:24 PM  
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Title: D:\TEMP\AS6245_01D.cal  
Date: 7/23/01  
Time : 05:21:25 PM  
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Title: D:\TEMP\AS6261_01C.cal  
Date: 7/23/01  
Time : 05:22:16 PM  
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Title: D:\TEMP\AS6262_01C.cal  
Date: 7/19/01  
Time : 02:05:07 PM  
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Title: C:\home\cms\benedil\view\9020-6324_01.DWG  
Date: 7/23/01  
Time : 05:23:05 PM  
DoTwnilotaldefr:omDW:w\wT.SEomManuPals\.cAomS. A6ll M4an6ua4ls_Se0ar1chGAnd.dDowwngload.  
Date: 7/23/01  
Time : 05:23:33 PM  
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Title: D:\TEMP\BD6464_01A.cal  
Date: 7/23/01  
Time : 05:24:13 PM  
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Title: D:\TEMP\IS6718_01A.cal  
Date: 7/23/01  
Time : 05:24:51 PM  
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Title: D:\TEMP\OD6355_01A.cal  
Date: 7/23/01  
Time : 05:25:30 PM  
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Title: D:\TEMP\OD6355_02A.cal  
Date: 7/23/01  
Time : 05:26:07 PM  
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Title: D:\TEMP\OD6355_03A.cal  
Date: 7/23/01  
Time : 05:26:42 PM  
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Title: D:\TEMP\OD6355_04A.cal  
Date: 7/23/01  
Time : 05:03:09 PM  
Title: c:\Dhoownmloadefr\ocmmWwsw.\Sbomeannuaels.dcoiml.\AvlliMeawnua\ls9S0ea0rch0A-n6d D4ow6n4loa_d.01.CAL  
5
4
3
2
1
REVISIONS  
LOC  
REV  
A
DESCRIPTION  
ECO. NO DRFT CHKR APP DATE  
CK 12/7/00  
73521  
RELEASE TO FACTORY  
FRONT PANEL  
R1  
1K  
+4.5V  
CHANNEL 1  
BILAT  
+
C1  
100/25  
R51  
22K  
C18  
R52  
47K  
D
C
B
A
R2  
2K  
R61  
60.4K  
R62  
C25  
+
J28  
M-114B  
CALL 1  
(SHT3,5D)  
+7V  
+14V  
+7V  
C19  
100pF  
100pF  
J1  
R
1
20.0K  
1%  
U3  
C20  
22/50  
P1  
JST-B-3B-ZR  
R3  
100  
C2  
4053  
1%  
2
3
+14V  
J8  
NC3FDH  
+
1
2
3
1
2
3
C24  
.1/50  
100pF  
T
4
X0  
X1  
Y0  
Y1  
Z0  
Z1  
LISTEN BUFFER  
CH.1  
R53  
R55  
22K  
12  
13  
2
C26  
X
Y
Z
TALK CH.1/4W-A  
+14V  
S
10/25  
R63  
C27  
5
14  
15  
4
3
2
1
2
3
+
COM  
CH 1  
CH 2  
+
+
1
U9A  
-
PANEL  
(SHT2,6D)  
LSN1  
(SHT3,7D)  
22K  
TALK  
BUFFER  
CH.1  
5
6
+
PM HI  
(SHT2,1D)  
MIC  
100  
22/50  
47/16  
7
NE5532  
U5B  
R64  
JACK  
TALK  
CH.2  
-
100K  
+7V  
C32  
.1/50  
1
TL072  
RP2A  
22K  
J9  
NC3MDH  
RP2C  
22K  
-
R58  
R59  
2
3
(SHT2,1D)  
(SHT2,1D)  
(SHT2,1D)  
REM MIC  
MIC LO  
MIC HI  
R49  
R50  
10K  
5
1
U6A  
TALK  
CH.3/  
LOOP  
THRU  
+
J6  
4WIRE A  
PROGRAMMING  
1
2
3
+7V  
60.4K  
1%  
C23  
10pF  
20.0K  
1%  
D6  
1N4004  
D7  
1N4004  
3
(SHT2,2C)  
HP L  
HP R  
4W-B  
22K  
C21  
R57  
TL072  
(SHT2,2C)  
RP1B  
RP1C  
RP1D  
(SHT3,  
2D)  
(SHT3,  
3
5
7
4
6
8
11  
10  
9
+14V  
XX  
YY  
ZZ  
DIFF MIC PRE AMP (+20dB)  
TC1  
TC2  
3
2
1
J24  
UNBAL/BAL  
+14V  
100pF  
MIC PROGRAMMING  
2D)  
2WIRE  
4WIRE  
C7  
10K TRIMPOT VM  
LIN  
1nF MONO  
929647-01-03  
UNBAL  
1
2
3
100K  
DYN  
R7  
R8  
R65  
C29  
R66  
HEADSET  
CONN  
BAL  
CHANNEL 2  
BILAT  
D15  
1N914  
CALL 2  
R76  
R77  
C36  
929647-01-03  
FB3  
KEY1  
3.01K  
1%  
J2  
47K  
+
(SHT3,5D)  
C28 100pF  
100pF  
301  
1%  
22K  
+7V  
JST-B-6B-ZR  
(SHT2,1D)  
KEY2  
FB4  
#73  
C3  
+
20.0K  
1%  
60.4K  
1%  
C30  
22/50  
1
2
3
4
5
6
D16  
1N914  
(SHT2,1D)  
R4  
100K  
100/25  
C4  
#73  
R6  
1K  
100pF  
R68  
LISTEN  
BUFFER  
CH.2  
-
R67  
22K  
6
5
+14V  
C34  
R78  
C35  
7
5
+
U1B  
1nF MONO  
+
+
+
7
U9B  
R5  
100K  
22K  
3
6
NE5532  
+
U5A  
-
(IFB-A)  
FB2  
#73  
FB1  
100  
22/50  
R9  
47/16  
1
NE5532  
C5  
LSN2  
R79  
C22  
2
-
100K  
(SHT2,6C)  
(SHT3,7D)  
+
.1/50  
R12  
1K  
TL072  
#73  
100/25  
301  
1%  
-
R74  
R75  
6
5
R10  
3.01K  
1%  
R69  
7
C6  
1nF MONO  
U6B  
+14V  
R13  
+
+7V  
TL072  
60.4K  
1%  
C33  
20.0K  
1% 10pF  
D8  
1N4004  
D9  
1N4004  
+14V  
TALK  
BUFFER  
CH.2  
22K  
R73  
22K  
R11  
620  
Q1  
R70  
10K  
C31  
100pF  
R80  
2N5087  
+7V  
Q2  
+14V  
C57  
+
10K TRIMPOT VM  
LIN  
R14  
22K  
+7V  
(SHT3,1B)  
CARB MIC  
R18  
22/50  
100 1/4W  
C38  
100pF  
R81  
47K  
2N5210  
CARB  
MIC  
CONN  
R19  
620  
R16  
22K  
CALL 3  
CHANNEL 3  
BILAT  
R15  
22K  
CARBON MIC SENSE  
(SHT3,5D)  
C37  
100pF  
22K  
R91  
60.4K  
R92  
C44  
+
+7V  
R17  
100 1/4W  
J3  
(SHT2,6B)  
PGMA  
SN37A-14B  
20.0K  
1%  
C11  
R21  
12K  
C39  
22/50  
C10  
.1/50  
R
1%  
1
C41  
.1/50  
+14V  
J10  
NC3FDH  
RB  
2
J4  
IFB A  
C43  
.1/50  
100pF  
.1/50  
R20  
100K  
D1  
1N4004  
TB  
R82  
22K  
R83  
22K  
3
4
5
+14V  
1
C9  
C45  
T
S
(TO CH 3)  
R94  
C46  
+
3
2
1
2
3
+
COM  
CH 3  
CH 4  
.1/50  
C12  
10/25  
+
(IFB-B)  
+14V  
LISTEN BUFFER  
CH.3  
1
+
U10A  
-
1
2
3
ON  
3
2
+
100  
22/50  
47/16  
C56  
.1/50  
NE5532  
LSN3  
U7A  
OFF  
-
U4  
R95  
100K  
(SHT2,6C)  
(SHT3,7D)  
+7V  
C51  
.1/50  
929647-01-03  
TL072  
R84  
4053  
+7V  
-
R89  
R90  
2
3
R85  
10K  
1
U8A  
X0  
X1  
Y0  
Y1  
Z0  
Z1  
+
12  
13  
2
+7V  
TALK  
BUFFER  
CH.3  
60.4K  
1%  
C42  
10pF  
3Vpp  
X
TALK CH.4  
+14V  
20.0K  
1%  
D10  
1N4004  
D11  
1N4004  
C136  
14  
15  
4
TL072  
(SHT2,7A)  
PGMB  
+7V  
22K  
R88  
+7V  
U2  
R23  
22K  
C40  
J5  
+14V  
4053  
R22  
22K  
.1/50  
14  
IFB B  
(TO CH 4)  
J7  
Y
4WIRE B  
R24  
100K  
+14V  
X0  
PROGRAMMING  
100pF  
12  
1
10K TRIMPOT VM  
LIN  
1
2
3
X
Y
Z
ON  
3
2
1
X1  
Y0  
Y1  
Z0  
Z1  
2WIRE  
4WIRE  
13  
2
5
MIC PRE/LIMITER  
OFF  
Z
3
929647-01-03  
+14V  
+7V  
5
15  
4
929647-01-03  
CHANNEL 4  
BILAT  
R38  
100  
RP3C  
1
6
11  
10  
9
XX  
YY  
ZZ  
C48  
R97  
47K  
R107  
60.4K  
R108  
C53  
R96  
22K  
C8  
.1/50  
NE5532  
+
RP3B  
RP3D  
5
3
7
4
8
+7V  
CALL 4  
C17  
3
+
20.0K  
1%  
+
(SHT3,5D)  
100pF  
C49  
22/50  
3
1
U1A  
1%  
2
C47  
100pF  
-
TC3  
(SHT3,2D)  
100K  
1/50  
11  
10  
9
XX  
YY  
ZZ  
HMS/PMS  
(SHT3,2D)  
100pF  
R98  
R99  
22K  
C54  
LISTEN  
BUFFER  
CH.4  
R109  
C55  
5
+
USM  
+
+
7
U10B  
-
(SHT2,4D)  
RP2F  
22K  
TALK  
BUFFER  
CH.4  
5
6
6
RP2I  
22K  
+
100  
22/50  
R26  
5.1M  
R27  
200  
Q3  
J305  
R28  
RP2E  
47/16  
1
7
7
NE5532  
+14V  
LSN4  
U7B  
6
1
+14V  
-
R110  
100K  
(SHT2,5C)  
(SHT3,7D)  
+7V  
22K  
D4  
1N914  
TL072  
R100  
TC4  
22K  
C15  
22K  
-
R105  
R106  
6
5
KEY4  
(SHT3,2D)  
+14V  
R101  
7
U8B  
(SHT2,1D)  
D5  
1N914  
+
+7V  
60.4K  
1%  
C52  
10pF  
20.0K  
1%  
D12  
1N4004  
D13  
1N4004  
R30  
TL072  
R29  
5.1M  
1nF  
22K  
10K  
R104  
KEY3  
+7V  
+14V  
C50  
100K  
(SHT2,1D)  
+7V  
RP2B  
22K  
RP2D  
22K  
+14V  
D2  
R31  
5.1M  
R37  
(SHT2,6D)  
SIDETONE  
C16  
.1/50  
R42  
100K  
100pF  
10K TRIMPOT VM  
LIN  
1N914  
100K  
NOTES: SEE SHEET 3 OF 3  
+14V  
C59  
10K TRIMPOT  
LIN  
+14V  
R32  
+
D14  
C13  
.1/50  
100pF  
R41  
VOX REC  
(SHT3,1A)  
+14V  
R33  
15K  
C14  
100/25  
+7V  
1N914  
CHK.  
DR.  
APP.  
Title  
THESE DRAWINGS AND SPECIFICATIONS ARE THE  
PRPOERTY OF TELEX COMMUINCATIONS, INC.AND  
SHALL NOT BE REPRODUCED, COPIED, OR USED  
FOR ANY PURPOSE WITHOUT EXPRESS WRITTEN  
CONSENT.  
470K  
R35  
100K  
R39  
2K  
C58  
CK  
Q5  
2N5210  
R34  
22K  
D3  
DATE  
SCALE  
SCHEMATIC DIAGRAM  
.1/50  
7/15/01  
1N914  
2N5210  
MOTHERBOARD MCE325  
R40  
30K  
R36  
10K  
DO NOT SCALE DRAWING  
Q4  
P/N  
DWG. NO.  
SIZE  
9027624501  
TELEX  
D
Sheet  
COMMUNICATIONS, INC.  
of  
1 3  
ORCAD GENERATED DRAWING  
FILE NAME: J/IC_GROUP/ECAD/SCHEMATIC/6245  
PLANT DIST:  
B.E.  
BURNSVILLE, MINNESOTA  
5
4
3
2
1
Download from Www.Somanuals.com. All Manuals Search And Download.  
5
4
3
2
1
+14V  
+7V  
C61  
U13  
4053  
J22  
745783-3  
+14V  
D
C
B
A
D
C
B
A
X0  
X1  
Y0  
Y1  
Z0  
Z1  
1nF  
C60  
+
R117  
R118  
RP6B  
12  
13  
2
SIDETONE  
X
Y
Z
USMB  
14  
15  
4
3
2
4
1
13  
25  
12  
24  
11  
23  
10  
22  
9
21  
8
20  
7
19  
6
18  
5
17  
4
16  
3
15  
2
14  
1
4W-A LO  
+14V IN  
ISO  
(SHT1,6A)  
C88  
.1/50  
SPKR MUTE  
REM MIC  
+18V IN  
4W-B LO  
4W-A LO  
KEY4  
10.0K  
1%  
NE5532  
10K  
(1D)  
10/25  
20.0K  
1%  
4W-A LSN  
RP6A  
R172  
C89  
1
3
2
+7V  
+
COM  
+
1
1
U17A  
-
4 WIRE A IN  
10K  
RP6C  
COM  
0dBu NOM  
(-10dBu TO  
+8dBu)  
301  
1%  
C63  
100pF  
10/25  
R173  
100K  
-
6
5
5
LSN1  
(-6dBu NOM)  
7
1
U11B  
4W-B HI  
4W-A HI  
KEY3  
(SHT1,4D)  
(SHT3,7D)  
-4dBu NOM  
(+6dBu pK)  
+
R170  
10K  
R171  
10K  
3
10K  
TL072  
(SHT1,6B)  
C62  
+
R119  
RP6D  
R174  
C90  
11  
10  
9
XX  
YY  
ZZ  
STC  
+
5
1
4W-A HI  
USM  
(SHT3,2D)  
C87  
+
KEY2  
(1D)  
10K  
301  
1%  
R175  
100K  
10/25  
20.0K  
1%  
10/25  
10/25  
KEY1  
LIST1  
J21  
R120  
10.0K  
1%  
C64  
1nF  
MOLEX FFC  
39-51-3304  
(SHT3,2D)  
HP COM  
MIC LO  
PM HI  
MIC HI  
CHS GND  
PM COM  
RP5A  
22K  
30  
29  
28  
27  
26  
25  
24  
23  
22  
21  
22  
RP5B  
22K  
RP5I  
22K  
(R1)  
VOL 1  
J19  
929647-01-04  
+7V  
PGM L  
C67  
(6A)  
R177  
100K  
TC2  
1
2
3
4
(R3)  
PGM  
VOL  
(1D)(SHT1,6D)  
(SHT3,2D)  
1nF  
+14V  
C66  
+
R124  
R125  
C97  
4W-B LO  
R176  
C91  
LM386  
5
100/25  
+
10.0K  
1%  
(1D)  
10/25  
20.0K  
1%  
2
3
R183  
10  
+14V  
C137  
.1/50  
(R2)  
VOL 2  
U18  
U14  
4053  
.1/50  
22K  
R181  
2.7  
TL072  
C93  
.1/50  
4 WIRE B IN  
C65  
+7V  
C92  
1nF  
C94  
C95  
HP L  
(SHT1,8D)  
.1/50  
0dBu NOM  
(-10dBu TO  
+8dBu)  
(SEE SD6246)  
10K AUDIO POT  
3 REQD  
C69  
100pF  
-
R182  
22K  
2
3
10/25  
4W-B LSN  
X0  
1
12  
13  
2
+
U11A  
LSN3  
X
.1/50  
+
14  
(SHT1,4B)  
(SHT3,7D)  
X1  
Y0  
Y1  
Z0  
Z1  
+14V  
C96  
.1/50  
C68  
+
R126  
R180  
1K  
(-6dBu NOM)  
+14V  
4W-B HI  
(SHT1,1C)  
2N5460  
Q10  
Y
Z
MONO SW  
15  
4
(1D)  
10/25  
20.0K  
1%  
R178  
1M  
1
RP7A  
C86  
MONO  
+
R127  
10.0K  
1%  
C70  
1nF  
5
2
1
LSN2  
(SHT3,5D)  
10K  
RP7B  
(SHT1,4C)  
(SHT3,7D)  
10/25  
3
C98  
.1/50  
11  
10  
9
3
4
5
1
XX  
YY  
ZZ  
LIST3  
(SHT3,2D)  
+7V  
10K  
RP7C  
PROGRAM A  
1
LIST2  
(SHT3,2D)  
10K  
C141  
.1/50  
+14V  
C72  
C105  
100/25  
+
J14  
SN37A-14B  
RP7D  
R184  
C99  
RP5H  
22K  
RP5G  
22K  
RP5C  
22K  
LM386  
U15  
4053  
R189  
10  
1
2
(1D)(SHT1,5A)  
(SHT3,2D)  
1nF  
C71  
+
R130  
R131  
5
U19  
R
(SHT3,7D)  
10K  
22K  
.1/50  
C100  
1nF  
R185  
100K  
1
3
X0  
X1  
Y0  
Y1  
Z0  
Z1  
R187  
2.7  
RB  
2
12  
13  
2
C101  
.1/50  
TC4  
1
2
3
4
LSN4  
10.0K  
1%  
X
10/25  
+14V  
TB  
20.0K  
1%  
C103  
10/25  
3
4
5
14  
15  
4
C102  
.1/50  
HP R  
(SHT1,4A)  
T
S
R188  
22K  
PGMA  
(SHT1,8C)  
+
J20  
(SHT1,5B)  
+14V  
Y
Z
+14V  
929647-01-04  
C104  
.1/50  
C74  
100pF  
-
R135  
6
5
1
R186  
1K  
7
U12B  
PGM R  
+
5
RP5F  
RP5E  
22K  
(6A)  
RP5D  
22K  
10K  
TL072  
22K  
+14V  
C73  
+
R132  
3
+7V  
(SHT3,2D)  
+7V  
11  
10  
9
XX  
YY  
ZZ  
LIST4  
R48  
10K  
10/25  
20.0K  
1%  
U33B  
(SHT3,2D)  
SPKR ON  
R133  
10.0K  
1%  
C75  
1nF  
5
C107  
4.7uF  
+
-
7
C143  
4.7uF  
SPKR DIM  
PROGRAM B  
6
(SHT3,2D)  
REAR PANEL  
R43  
20K  
LM833  
SPKR JACK  
+7V  
C81  
J23  
MLSS100-3  
J27  
J15  
SN37A-14B  
U34  
C82  
+
MN-114B  
R
1nF  
C77  
+
R138  
R139  
P23  
1
2
3
4
5
R
1
6
7
1
1
2
3
1
2
3
INA  
INB  
OUTA  
OUTB  
R157  
R47  
RB  
1/50  
2
2
5
3
T
S
10.0K 1%  
20K  
SPKR DIM  
ADJUST  
(MIN=6dB  
MAX=26dB)  
10/25  
TB  
20.0K  
1%  
3
4
5
T
S
C113  
BIAS  
VCC  
LM4752/TO  
20K TRIMPOT  
LIN  
R152  
200  
270pF  
+14V  
C76  
.1/50  
4
C79  
100pF  
-
R142  
10K  
2
3
1
U12A  
+
TL072  
C78  
+
R140  
C84  
U31A  
1
C109  
1000uF  
R153  
160K  
C142  
4.7uF  
PGMB  
3
2
C106  
4.7uF  
+
-
500pF  
20K  
(SHT1,6B)  
R44  
10/25  
20.0K  
1%  
E1  
E2  
R45  
2.7  
R156  
+14V  
R46  
20K  
2.7  
R141  
10.0K  
1%  
C80  
1nF  
R154  
LM833  
17-25VDC SOURCE  
J16  
929647-01-03  
47K  
R25  
10K  
ON  
C83  
10/25  
+7V  
+7V  
R155  
C108  
100uF  
C110  
0.1uF  
C111  
0.1uF  
1
2
3
PGM ASSIGN  
TO HDST L  
+
-
6
5
PGM L  
7
U16B  
OFF  
(4D)  
R54  
+
47K  
20K  
TL072  
C112  
J17  
929647-01-03  
+7V  
ON  
270pF  
1
2
3
PGM ASSIGN  
TO HDST R  
PGM R  
(4B)  
OFF  
NOTES: SEE SHEET 3 OF 3  
J18  
929647-01-03  
R56  
0
1
2
3
PGM ASSIGN  
TO SPEAKER  
PAGE  
Title  
MOTHER BOARD MCE325 2  
REV  
DWG. NO.  
A
9027624501  
5
4
3
2
1
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5
4
3
2
1
U23  
1
2
6
7
16  
15  
14  
13  
12  
11  
10  
9
(SHT1,6D)  
(SHT1,6D)  
(SHT1,6A)  
(SHT1,5A)  
(SHT2,6B)  
(SHT1,8B)  
(SHT2,6D)  
TC1  
TC2  
TC3  
TC4  
SPKR ON  
HMS/PMS  
STC  
CLK  
DI  
STR  
EN  
D0  
D1  
D2  
D3  
D4  
D5  
D6  
D7  
+5V  
CALL LIGHT MUX  
R198  
270K  
C134  
.1/50  
+5V  
C139  
5
DO  
7
D
C
B
A
D
C
B
A
U30A  
4093  
SPKR DIM  
(SHT2,6B)  
C140  
.1/50  
40  
+14V  
U29  
.1/50  
2
1
U21  
4053  
3
3
8
4
+5V  
.
VCC  
3
39  
38  
VOX IN  
VPP  
OSC1  
OSC2  
Y1  
4.00MHz  
VDD  
R200  
2.2M  
GND  
X0  
X1  
Y0  
Y1  
Z0  
Z1  
(2A)  
12  
13  
2
28  
27  
26  
25  
24  
23  
22  
21  
C115  
10pF  
PC0  
PC1  
PC2  
PC3  
PC4  
PC5  
PC6  
PC7  
X
14  
UCN5821A  
14  
15  
4
+5V  
11  
10  
9
8
7
6
5
4
C116  
10pF  
(SHT2,3C)  
(SHT1,4D)  
(SHT1,4C)  
(SHT1,4C)  
(SHT1,4B)  
MONO  
CALL 1  
CALL 2  
CALL 3  
CALL 4  
PA0  
PA1  
PA2  
PA3  
PA4  
PA5  
PA6  
PA7  
U24  
(SHT1,4D)  
,(SHT2,5D)  
LSN1  
LSN2  
LSN3  
LSN4  
Y
Z
1
2
6
7
16  
15  
14  
13  
12  
11  
10  
9
(SHT2,6D)  
LIST1  
LIST2  
LIST3  
LIST4  
CALL CTL1  
CALL CTL2  
CLK  
DI  
STR  
D0  
D1  
D2  
D3  
D4  
D5  
D6  
D7  
1
(SHT1,4C),(SHT2,5C)  
(SHT1,4B),(SHT2,6C)  
(SHT1,4B),(SHT2,5C)  
(SHT2,7C)  
(SHT2,7C)  
(SHT2,6B)  
(7D)  
5
EN  
+5V  
3
5
(7D)  
DO  
.
29  
30  
31  
32  
33  
34  
35  
36  
(2B)  
DSW5  
PD0/RDI  
+14V  
11  
10  
9
12  
13  
14  
15  
16  
17  
18  
19  
XX  
YY  
ZZ  
(TO 2D)  
CALL CTL1  
CALL CTL2  
PD1/TDO  
PD2/MISO  
PD3/MOSI  
PD4/SCK  
PD5/SS  
TCMP  
PB0  
PB1  
PB2  
PB3  
PB4  
PB5  
PB6  
PB7  
+14V  
E16  
R199  
10K  
3
8
4
(TO 2D)  
+17-25VDC  
VCC  
E10  
E11  
E13  
GND  
E14  
RP2G  
22K  
+5V  
E15  
(AUDIBLE)  
RP2H  
22K  
UCN5821A  
DSW7  
PD7  
J21  
39-51-3304  
MOLEX FFC  
1
2
3
4
5
6
7
8
9
+5V  
37  
2
TCAP  
IRQ  
E12  
U25  
1
+5V  
+
RESET  
VSS  
+14V  
RP14A  
RP14B  
RP14C  
RP14D  
RP14E  
RP15B  
RP15C  
RP15D  
RP15E  
680  
680  
680  
680  
680  
680  
680  
680  
680  
1
16  
1
3
5
7
9
3
5
7
9
2
4
6
8
C135  
22/50  
MIC ON  
SPKR ON  
PANEL MIC  
CALL LIGHT  
CH 4  
CH 3  
CH 2  
CLK  
2
D0  
D1  
D2  
D3  
D4  
D5  
D6  
D7  
C117  
15  
14  
13  
12  
11  
10  
9
DI  
6
STR  
7
MC68HC7058  
10pF  
R207  
EN  
20  
FRONT  
PANEL  
LEDS  
10  
5
4
6
8
DO  
+5V  
C118  
.1/50  
+5V  
CH 1  
CALL RED  
100K  
10  
10  
R201  
3.01K  
R212  
270K  
U30B  
4093  
3
.
4
+5V  
VCC  
C119  
C85  
.1/50  
R208  
5
6
1%  
-
C120  
R211  
22K  
2
3
4
8
GND  
1
U16A  
10K  
R215  
100K  
.01/50  
+
UCN5821A  
TL072  
100pF  
MYLAR  
U22  
MC33064  
C121  
10pF  
R214  
R209  
1K  
+5V  
2
1
R213  
270K  
+14V  
IN  
RSET  
10K  
+7V  
J21  
39-51-3304  
MOLEX FFC  
RP8A  
22K  
RP8B  
22K  
RP8C  
22K  
RP8D  
22K  
RP8E  
22K  
RP8F  
22K  
RP8G  
22K  
RP8H  
22K  
RP8I  
22K  
C122  
.1/50  
N.C.  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
RP10B  
RP10A  
RP10C  
RP10D  
RP11D  
RP11C  
RP11B  
RP11A  
100K  
4
6
7
3
3
5
8
4
MIC ON  
SPKR ON  
PANEL MIC  
CALL LIGHT  
CH 4  
CH 3  
CH 2  
CH 1  
100K  
1
8
5
1
2
+5V  
100K  
FRONT  
PANEL  
SWITCHES  
C138  
100K  
7
100K  
100K  
6
.1/50  
4
100K  
100K  
2
3
1
2
O
I
S
C
U30C  
U28  
8
9
93C56  
10  
+5V  
RP9H  
22K  
RP9F  
22K  
RP9G  
22K  
RP9A  
22K  
RP9B  
22K  
RP9C  
22K  
RP9D  
22K  
RP9E  
22K  
4093  
RP9I  
22K  
(SHT1,8D)  
(SHT2,1D)  
(SHT1,7C)  
(SHT2,1D)  
(SHT2,1D)  
RP12A  
RP12B  
RP12C  
RP12D  
100K  
100K  
100K  
100K  
U30D  
4093  
1
3
5
7
2
4
6
8
REM MIC  
CARB MIC  
ISO  
SPKR MUTE  
S1  
12  
13  
11  
K40-8S  
1
2
3
4
5
6
7
8
16  
15  
14  
13  
12  
11  
10  
9
(5D)  
(5D)  
DSW5  
ANALOG MID  
VOLTAGE  
DSW7  
VOX IN  
R264  
220K  
C129  
100/25  
(7D)  
+
-
+
6
5
7
+7V  
SOURCE  
U17B  
OFF  
ON  
17-25VDC SOURCE  
R269  
10K  
NE5532  
D21  
REAR PANEL MOUNTED  
R265  
220K  
+18V IN  
(SHT2,1D)  
E6  
VOX REC  
T1  
TO-10R-RT  
15VA  
1N4004  
D20  
1N4004  
(SHT1,1D)  
+14V IN  
(SHT1,4A)  
CR1  
KBL005  
SOURCE  
+14V  
+5V  
F1  
R268  
200  
1
2
SOURCE  
+4.5V  
(TO ELECTRET PANEL  
MIC VIA NETWORK)  
50VRRM  
4.0A  
HOT  
HEATSINK  
D22  
1N4004  
0.5A SBLO  
LM317T  
U27  
IN  
15VAC  
15VAC  
LM317T  
E7  
U26  
-
+
4
2
3
2
3
2
SOURCE  
(TO DIGITAL IC'S)  
+5V  
IN  
OUT  
OUT  
AC PLUG  
EARTH  
R263  
301  
1%  
R267  
301  
1%  
+
3
+
+
C133  
100/25  
C125  
4700/35  
C128  
10/25  
C130  
.1/50  
C132  
.1/50  
E8  
+
+
909  
1%  
3.01K  
1%  
NEUTRAL  
R262  
C127  
10/25  
R266  
C131  
10/25  
E9  
GND TP  
R261  
22K  
C126  
.1/500  
2. CAPACITANCE VALUES ARE SHOWN IN MICROFARADS/VOLTS.  
1. ALL RESISTORS ARE CARBON FILM,1/8W,5%.  
NOTES: UNLESS OTHERWISE SPECIFIED  
PAGE  
Title  
MOTHER BOARD MCE325 3  
REV  
DWG. NO.  
A
9027624501  
5
4
3
2
1
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Date: 7/23/01  
Time : 05:19:08 PM  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Title: D:\TEMP\SD6246_01A.cal  

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