Alternate Microphones And Installation; 4 Wire Mic Cable; Your Transceiver Microphone Schematic - Galaxy DX 979 Service Manual

2.4 ALTERNATE MICROPHONES AND INSTALLATION

For best results, the user should select a low impedance dynamic type microphone or a transistorized
microphone. Transistorized type microphones have a low output impedance characteristic. 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 the fourth is for receiving control.
The microphone should provide the functions shown in the schematic below (Figure 2-3).
Figure 2-4 Microphone plug and pin numbers viewed from rear of pin receptacle.

4 WIRE MIC CABLE

Pin Number
1
2
3
4
Figure 2-3 Your Transceiver Microphone Schematic
Mic Cable Lead
Audio Shield
Audio Lead
Transmit Control
Receive Control
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