I have a Shure WH20 TQG headset mic with a 4 pin TA4F connector on it. I'm looking to make an adaptor up so I can use this mic as a wired mic.This can be done. Fabricate the adapter as follows:
1) TA4M connector will mate with TA4F connector on WH20 cable.
2) Male XLR will mate with the female XLR on a mic cable.
3) Wire as follows:
TA4M pin 1 to cable shield to male XLR pin 1
TA4M pin 2 - unused
TA4M pin 3 to cable inner conductor to male XLR pin 2
TA4M pin 4 - unused
Wire a jumper from male XLR pin 3 to male XLR pin 1
NTOE WELL: When using this adapter, make certain the mixer input does NOT provide phantom power. If it does, the WH20 may be damaged.
Using this adapter the WH20 will provide a low impedance, unbalanced mic level signal. If you encounter noise interference problems because the signal is unbalanced, insert a 150 ohm / 150 ohm (XLR in / XLR out) isolation transformer at the end of the adapter. This transformer will also protect the WH20 from phantom power.