Radio Shack / Realistic Microphone Pin Outs.
For: HTX-212, HTX-242.

Never ground pin 7 or damage to the regulator will occur.

8 pin Modular Pin Signal
connector 1Tone
2Common Ground
3CPU Clock
4Control (212 schematic shows sp?)
5Mic Audio
(connect to pin 2 for TX)
7+7.5v (212 user manual, schematics for both models show 5v!)
8Data in from microphone.

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