Manuals / Telex / Home Audio / Stereo Amplifier

Telex MCE325 manual ISO Test, Remote Mic Switch Test, Program Lockout Test, Noise Checks

Models: MCE325

1 85

Download 85 pages 25.05 Kb

Page 50

ISO Test

ISO Test

1Set DIP switch DS3 to off (two-channel, two-wire mode).

2Set DIP switch DS5 to on (talk muted during ISO).

3Set all TALK and LISTEN buttons to on.

4Connect 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.

5Remove the 100 ohm resistor across the ISO input.

6Reset DIP switch DS3 to on and DS5 to off.

Remote Mic Switch Test

1Set all buttons to off.

2Connect 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.

3Remove the 100 ohm resistor.

Program Lockout Test

1Set DIP switch DS4 to on (front panel setup lockout enabled).

2Press and hold the CALL button for ten seconds, and verify that the MCE325 does not enter program mode.

3Reset DS4 to off.

Noise Checks

1Connect a 150 ohm load across the dynamic mic input (J2 pins 1 and 2).

2Connect an 8 ohm load across the speaker output.

3Connect 51 ohm loads across the left headphone output (J2 pins 3 & 4) and right headphone output (J2 pins 3 &5).

4Terminate each intercom channel into 200 ohms.

5Set the MIC ON button to on.

6Set the SPKR ON button to on.

7Set all other front panel buttons to off.

8Set 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.

9Set 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.

4-12C S I - 2 0 0 U s e r I n s t r u c t i o n s

Image 50

Telex MCE325 manual ISO Test, Remote Mic Switch Test, Program Lockout Test, Noise Checks

Contents

PROGRAMMABLE USER STATION MODEL MCE325USER INSTRUCTIONS COPYRIGHT NOTICE WARRANTY INFORMATIONPROPRIETARY NOTICE UNPACKING AND INSPECTIONRETURN SHIPPING INSTRUCTIONS End-UserLicense Agreement for Telex Software Installation TABLE OF CONTENTSDescription & Specifications Maintenance OperationParts Lists DiagramsPage Description DESCRIPTION & SPECIFICATIONSFeatures GeneralConnections, Inputs and Outputs Front Panel FeaturesVolume Controls Channel Selector and Operation ButtonsExternal Program Input Rear Panel FeaturesIntercom Lines Auxiliary Connector PowerMounting Configuration ProgrammingMicrophone Preamplifier MCE325 SpecificationsPower and Mechanical Headphone AmplifierMCS325 Specifications ConnectorsFigure 1.3 Standard four-channel, two-wireconfiguration 1-8 M C E 3 2 5 U s e r I n s t r u c t i o n s Figure 1.8 Multiple interconnected stations using one four-wireintercom channel and two two-wirechannels for 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 Figure 1.11 MCE325 button configurations 1-12 M C E 3 2 5 U s e r I n s t r u c t i o n s General INSTALLATIONInternal Programming and Adjustments S E C T I O NDefault Setting Switch NumberSwitch Function Figure 2.1 Top cover removalJumper Number Table 2.2 Jumper functions and default settingsDefault Setting Jumper Function2-4 C S I - 2 0 0 U s e r I n s t r u c t i o n s Remote Talk-offDS7 Front Panel Setup Mode Lock-outDS4ISO DS5 VOX DS8Speaker Dim Adjustment R157 Mechanical InstallationHeadphone Sidetone Trimmer Adjustment R37 Program Assignment - IFB Option J4, J5, J16-J18Figure 2.3 Mounting configurations Connector Pin-outs Electrical InstallationAC Power and Fuse Four-wireOutput TerminationProgram Inputs, J14 and J15 Auxiliary Connector, J22Four-WireChannel A and B Input External Speaker, J27ISO Connection Remote Microphone SwitchKey outputs - Expanded IFB Option External HeadsetExternal DC Power Source Front Panel Headset ConnectionsUnswitched Microphone Output External Electret MicrophoneFUNCTION Table 2.9 Carbon-microphoneheadset connectorSECTION Carbon microphoneGeneral LED IndicatorsOPERATION Operating InstructionsPanel Mic/Headset Mic Selection Volume AdjustmentFront Panel Sidetone Nulling Trimmer Adjustment Microphone On/OffActivating Setup Mode Sending and Receiving Call SignalsUsing the Talk-OffFeature Menu Selection/Ending SetupChannel ID Call DisableLatch Disable Four-channelListenReset Instant Mic3-6 C S I - 2 0 0 U s e r I n s t r u c t i o n s Corrective Maintenance MAINTENANCEPreventive Maintenance AccessPower Supply Test Test and Adjustment ProceduresCleaning Test EquipmentInitial Configuration Keying Output TestFour-Channel, Two-WireMode Frequency Response and Level Check, Mic to LineSidetone Null Test and Adjustment Two-Channel, Four-WireModeTrue Sidetone Adjust Program A to Left Headphone Program to Speaker IFB TestProgram B to Right Headphone IFB BIFB A Four-WireA Input to Left HeadphoneFour-WireB input to Right Headphone VOX Test Panel Mic to Channel TestCarbon Mic to Channel Test Mic Kill Receive TestCall Receive Test Mic Kill Transmit TestCall Transmit Test Program Lockout Test Remote Mic Switch TestISO Test Noise Checks15Turn all buttons off Page Final Assembly, MCE325 PARTS LISTSPackaging Assembly S E C T I O NItem No Front Panel AssemblyTable 5.3 Reference AS6261 Drawing, Section DescriptionMain PC Board Assembly Back Panel AssemblyHeatsink Assembly Item NoC104 Capacitor, EL, 10µF Capacitor, Mylar, 1nF Diode, 1N4004 Transistor, 2N5210 R170 R267 Resistor, CF, 22K Ohm, 5%, 1/8W IC, Dual Low-noise Op-Amp,NE5532N Ref No PC Board Assembly, Front PanelTable 5.7 Reference AS6246 Drawing, Section DescriptionPage DIAGRAMS S E C T I O N6-2 C S I - 2 0 0 U s e r I n s t r u c t i o n s Time 05 20 45 PM Date 7/23/01Title D \TEMP\AS6246 01B.cal Date 7/23/01 Title D \TEMP\AS6245 01D.calTime 05 27 24 PM Date 7/23/01 Title D \TEMP\AS6261 01C.calTime 05 21 25 PM Date 7/23/01 Title D \TEMP\AS6262 01C.calTime 05 22 16 PM Title C \home\cms\benedil\view\9020-6324 01.DWG Date 7/19/01Time 02 05 07 PM Date 7/23/01 Title D \TEMP\AS6464 01G.dwgTime 05 23 05 PM Date 7/23/01 Title D \TEMP\BD6464 01A.calTime 05 23 33 PM Date 7/23/01 Title D \TEMP\IS6718 01A.calTime 05 24 13 PM Date 7/23/01 Title D \TEMP\OD6355 01A.calTime 05 24 51 PM Date 7/23/01 Title D \TEMP\OD6355 02A.calTime 05 25 30 PM Date 7/23/01 Title D \TEMP\OD6355 03A.calTime 05 26 07 PM Date 7/23/01 Title D \TEMP\OD6355 04A.calTime 05 26 42 PM Date 7/23/01 Title c \home\cms\benedil\view\9000-6464 01.CALTime 05 03 09 PM MCE325 SCHEMATIC DIAGRAMMOTHERBOARD 9027624501MCE325 MOTHER BOARD9027624501 TitleTitle MOTHER BOARD MCE3259027624501 DWG. NODate 7/23/01 Title D \TEMP\SD6246 01A.calTime 05 19 08 PM