Section VI Appendix (Continued)

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 five-lead cable. The audio conductor and its shielded lead comprise two of the leads. The third lead is for receive control, the forth is for grounding and fifth is for transmit control.

The microphone should provide the functions shown in schematic below.

 

5 WIRE MIC CABLE

Pin Number

Mic Cable Lead

1

Audio Lead

2

Audio Shield

3

Receive Control

4

Grounding

5

Transmit Control

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 1. Cobra 2010 GTL WX microphone schematic.

If the microphone to be used is provided with pre-cut 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 (see Fig. 2.)

2.All leads should be cut to the same length. Strip the ends of each wire 1/8” and tin the exposed wire.

Before beginning the actual wiring, read carefully, the circuit and wiring informa- tion provided with the microphone you select. Use the minimum lead required in soldering the connections. Keep the exposed wire lengths to a minimum to avoid shorting when the microphone plug is reassembled.

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Cobra Electronics 2010 GTL WX operating instructions Alternate Microphones and Installation, Wire MIC Cable