Wiring diagram for Lafayette Comstat 23 Mark V Lafayette Mic

[danmcclain]

I would appreciate any and all information on how to wire a Lafayette mic to this radio. The radio will not receive in the cb mode. There is no relay in this radio so the switching is done in the mic. The Lafayette mic wire colors a red, black, white, and shield. The mic plug is 4 pin. Thanks...Dan

 

[loosecannon]

Dan,

in order to figure out which color wire on your mic does what, you just need a voltmeter set to read continuity.

one wire will be a copper shield wrapped around another wire.
the copper shield is ground.
the wire it is wrapped around is the audio wire.

now with your voltmeter, connect one lead to the shield, and touch the other lead to one of the remaining wires.

the wire that shows continuity without the mic button pressed is the receive wire.
the wire that shows continuity with the mic button pressed is the transmit wire.
LC

 

[sunbulls]

Pin 1...Audio
Pin 2...Transmit
Pin 3...Receive
Pin 4...Ground / Shield

A stock mic on that radio requires a High z crystal or ceramic cartridge, otherwise you will need a power mic to makeup for the impedance mismatch.

 

[loosecannon]

here is an excerpt from the Turner mic wiring handbook:



we can also figure out what pin does what on the mic jack on the radio if this doesn't help.
LC

 

[danmcclain]

Dan,

in order to figure out which color wire on your mic does what, you just need a voltmeter set to read continuity.

one wire will be a copper shield wrapped around another wire.
the copper shield is ground.
the wire it is wrapped around is the audio wire.

now with your voltmeter, connect one lead to the shield, and touch the other lead to one of the remaining wires.

the wire that shows continuity without the mic button pressed is the receive wire.
the wire that shows continuity with the mic button pressed is the transmit wire.
LC

Thank you Loosecannon for your input. Dan

 

[danmcclain]

Pin 1...Audio
Pin 2...Transmit
Pin 3...Receive
Pin 4...Ground / Shield

A stock mic on that radio requires a High z crystal or ceramic cartridge, otherwise you will need a power mic to makeup for the impedance mismatch.

View attachment 58062

thank you Sunbulls for your info...Dan

 

[sunbulls]

This is my enhanced and spliced schematic for anyone that may want to restore this radio in the future.

 

[danmcclain]

This is my enhanced and spliced schematic for anyone that may want to restore this radio in the future.
View attachment 58077

Thanks for the schematic, it will come in handy...Dan