Baofeng / Wouxun common headset wire colours / assignments / PTT control

Green  2.5mm tip     rx audio +
 Blue  2.5mm sleeve  rx audio gnd,  ptt GND, rig gnd
 Bare  3.5mm sleeve  tx audio gnd,  ptt +V, NB NOT rig ground
  Red  3.5mm ring    tx audio +

To key the PTT, current must be able to flow from Bare (3.5mm sleeve) to Blue (2.5mm sleeve).

That is, either short Bare and Blue (sleeve to sleeve), or a current should be able to flow from Bare (3.5mm sleeve) to NPN transistor collector, to emittor, to Blue (2.5mm sleeve). An NPN transistor conducts from collector to emitter when a voltage is applied between base (+v) and collector (gnd)) – 5V + 1k resistor.

In other words:
The radio puts 3.3V down the Bare (3.5mm sleeve) conductor.
To key up, this must be shorted to the Blue (2.5mm sleeve) conductor.

RX audio is present between Green (2.5mm tip) and Blue (2.5mm sleeve)

TX audio should be pushed in to Red (3.5mm ring) and Bare (3.5mm sleeve)

1 thought on “Baofeng / Wouxun common headset wire colours / assignments / PTT control”

Leave a Reply

Your email address will not be published. Required fields are marked *