Page 3 - RETURN SHIPPING INSTRUCTIONS
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 DepartmentTelex Communications, Inc.Telephone: (877) 863-4169Fax: (800) 32...
Page 4 - End-User License Agreement for Telex® Software
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 ...
Page 5 - Description & Specifications
i T ABLE OF C ONTENTS Description & Specifications 1-1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....
Page 6 - Operation
ii Unswitched Microphone Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11External DC Power Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11Remote Speaker Mute Control . . . . . . . . . . . . . . . ....
Page 7 - Parts Lists
iii IFB A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9 Level and Frequency Response Check, Four-Wire Input to Headphone . . . . . . . . . . . . . . . . . . . . . . . . 4-9 Four-Wire A Input to Left Headphone . . . . . . . . . ....
Page 9 - E C T I O N; ESCRIPTION; Description; General
1-1 S E C T I O N C HAPTER 1 D ESCRIPTION & S PECIFICATIONS 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 ...
Page 10 - Front Panel Features; Channel Selector and Operation Buttons; Volume Controls; PGM VOL; Sidetone Nulling Trimmers; Connections, Inputs and Outputs; Front Panel; DYNamic MIC HEADSET
1-2 M C E 3 2 5 U s e r I n s t r u c t i o n s 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; print...
Page 11 - Rear Panel Features; Intercom Lines
1-3 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-wi...
Page 12 - Speaker Output; Programming
1-4 M C E 3 2 5 U s e r I n s t r u c t i o n s 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 wi...
Page 13 - MCE325 Specifications
1-5 MCE325 Specifications General Bridging Impedance (to line) 10,000 ohms typical Noise Contribution to 200-ohm Line -90 dBu Call Signal Frequency 20 kHz, crystal controlled Talk-off Frequency 24 kHz, crystal controlled Microphone Preamplifier Maximum Voltage Gain 54 dB Frequency Response 100 Hz to...
Page 14 - Connectors; MCS325 Specifications
1-6 M C E 3 2 5 U s e r I n s t r u c t i o n s Connectors Intercom Line Connector XLR type, 3-pin (male-female loop through on two-wirechannel 1 and 2, or four-wire channel A; Female only ontwo-wire channel 3 and 4, or four-wire channel B Dynamic Mic XLR type, 6-pin female Carbon Mic ¼-inch phone j...
Page 21 - NSTALLATION; Internal Programming and Adjustments; WARNING
2-1 S E C T I O N C HAPTER 2 I NSTALLATION 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 nece...
Page 26 - Headphone Sidetone Trimmer Adjustment (R37); Mechanical Installation
2-6 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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 fou...
Page 28 - Electrical Installation; AC Power and Fuse
2-8 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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 vo...
Page 29 - Auxiliary Connector, J22; Four-Wire Channel A and B Input
2-9 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 ...
Page 30 - Key outputs – Expanded IFB Option
2-10 C S I - 2 0 0 U s e r I n s t r u c t i o n s Key outputs – Expanded IFB Option Four logic-type outputs are available at pins 6, 7, 19, and 20 of the auxiliary connector: 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 ...
Page 31 - Front Panel Headset Connections
2-11 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 hig...
Page 33 - PERATION; Momentary/Latching Button action; LED Indicators
3-1 S E C T I O N C HAPTER 3 O PERATION 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 fr...
Page 34 - Panel Mic/Headset Mic Selection; Volume Adjustment; Front Panel Sidetone Nulling Trimmer Adjustment
3-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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...
Page 35 - Front Panel Programming; Activating Setup Mode; Submenus
3-3 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 c...
Page 36 - Channel ID; Mono; Latch Disable
3-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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 sele...
Page 39 - AINTENANCE; Preventive Maintenance; Factory Support Information; Access; Front Panel Removal
4-1 S E C T I O N C HAPTER 4 M AINTENANCE 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. At...
Page 40 - Cleaning; Test and Adjustment Procedures; Notes
4-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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...
Page 41 - Initial Configuration; Keying Output Test
4-3 4 Measure the ripple. V ripple = 140 mVp-p 5 Measure the regulated DC voltage at U26 pin 2. (There should be no ripple.) V U26-2 = 13.85 ±0.3 VDC 6 Measure the mid-voltage source at U17 pin 7. V U17-7 = 6.93 ±0.3 VDC 7 Measure the +5 V source at the output of U27 pin 2. V U27-2 = 5.0 ±0.3 VDC In...
Page 42 - Frequency Response and Level Check, Mic to Line
4-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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: k...
Page 43 - Sidetone Null Test and Adjustment
4-5 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 ...
Page 44 - True Sidetone Adjust
4-6 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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, “MON...
Page 45 - Level and Frequency Response Check, Intercom Channel to Speaker; Program A to Left Headphone
4-7 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 s...
Page 46 - Program B to Right Headphone; IFB Test; IFB B
4-8 C S I - 2 0 0 U s e r I n s t r u c t i o n s 11 Restore 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 ±...
Page 47 - IFB A; Four-Wire A Input to Left Headphone
4-9 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 t...
Page 48 - Panel Mic to Channel Test
4-10 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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 c...
Page 50 - ISO Test
4-12 C S I - 2 0 0 U s e r I n s t r u c t i o n s 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 1...
Page 53 - ARTS
5-1 S E C T I O N C HAPTER 5 P ARTS L ISTS Packaging Assembly (9000-6464-00) Final Assembly, MCE325 (9010-6464-00) Table 5.1 Reference PD6464 Drawing, Section 6 Item No. Description RTS Part No. 1 User Manual, MCE325 User Station 9350-6464-00 2 Label, Warning 9170-6739-00 3 Final Assy, MCE325 9010-6...
Page 67 - IAGRAMS
Page 82 - CK; SCHEMATIC DIAGRAM; Title; DO NOT SCALE DRAWING; TELE; ORCAD GENERATED DRAWING
5 5 4 4 3 3 2 2 1 1 D C B A BILAT TALK (SHT3,7D) (SHT2,1D) BAL (SHT3,5D) CH.3 2D) CH.3 (SHT2,1D) LISTEN BUFFER (SHT3, CH.4 MIC CH.1 CH 4 (SHT2,1D) LISTEN 2D) BUFFER LISTEN BUFFER (TO CH 4) CH 3 (SHT3,2D) CH.4 (SHT3, (SHT2,6D) TALK 4WIRE OFF COM (SHT3,2D) BUFFER JACK CHANNEL 3 2WIRE ON CH 2 FRONT PAN...
Page 83 - MOTHER BOARD
5 5 4 4 3 3 2 2 1 1 D D C C B B A A (SHT3,2D) ON PGM ASSIGN (6A) (SHT3,2D) 22 28 0dBu NOM (SHT3,2D) (SHT1,4B) 29 (-6dBu NOM) (SHT3,7D) (1D) 4 WIRE B IN (1D)(SHT1,6D) (+6dBu pK) MAX=26dB) (-10dBu TO+8dBu) PGM ASSIGN (SHT3,5D) TO HDST L TO SPEAKER -4dBu NOM T S (SHT1,4A) (4B) PROGRAM B (1D) (6A) (SHT3...
