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OPERATION
A
ALTERNATE MICROPHONES AND INSTALLATION
For best results, the user should select a Condenser type microphone. The microphones
must be provided with a four-lead cable. The audio conductor and its shielded lead
Comprise two of the leads. The third lead is for transmit control and fourth is for receiving
Control
The microphone should provide the functions shown in schematic below.
4 WIRE MIC CABLE
Pin Number
Mic Cable Lead
1
Audio Shield
2
Audio Lead
3
Transmit Control
4
Receive Control
Fig. 1
Transceiver Microphone Schematic Diagram
If the microphone to be used is provided with precut leads, they must be revised as follows.
1. Cut leads so that they extend 7/16" beyond the plastic insulating jacket of the microphone
cable.
2. All leads should be cut to the same length. Strip the ends of each wire 1/8" and tin the
exposed wire.
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OPERATION
A
Before beginning the actual wiring, read carefully the circuit and wiring information provided
with the microphone you select. Use the minimum heat required in soldering the connections.
Keep the exposed wire lengths to a minimum to avoid shorting when the microphone plug is
reassembled.
Fig. 2
Microphone plug wiring
To wire the microphone cable to the plug provided, proceed as follows:
1. Remove the retaining screw.
2. Unscrew the housing from the pin receptacle body.
3. Loosen the two cable clamp retainer screws.
4. Feed the microphone cable through the housing, knurled ring as shown Figure 2.
