Radio Shack HTX-200 Owner's Manual page 15

Caution: Use only microphone and speaker accessories that do
not share a common ground for the speaker and the microphone.
Doing otherwise might damage the transceiver.
Note: Inserting a headset's plug automatically disconnects the in-
ternal speaker.
You can also connect an optional mono earphone to the SPK
jack. This lets you use the transceiver's push-to-talk button to
transmit as usual. Your local RadioShack store carries a wide se-
lection of suitable communications headsets, earphones, and
separate components.
The following schematic diagram shows the typical wiring for a
suitable external mic and speaker.
Speaker Plug
MIC Plug
Barrel
Tip
External Microphone
Barrel
Tip
PTT
External Speaker
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