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I've ordered one of these: https://www.amazon.com/gp/product/B074Z1LDY2/, a tactical throat mic (and earpiece speaker) which is intended to be used with Kenwood two-way radios (and other compatible models). I'm interested in using this with conventional CTIA TRRS inputs/outputs as found on cell phone and laptops.

I know the pin-outs are incompatible as they are so I know I need to re-wire at bare minimum. What I'm trying to discover is how to tell if I need some capacitors and resistors or a full, externally powered circuit to support the mic (my primary interest, the speaker is less interesting to me).

I have a mid-level multi-meter and no oscilloscope. I know the pin-outs for these generally:

Kenwood two-way pinouts: Kenwood two-way two-pin pinouts

CTIA cell phone TRRS pinouts CTIA standard TRRS pinout

How can I best reverse engineer what the two-way radio mic is expecting and how to hook it up to what the cell phone is providing WRT to power? I've not been able to find any references on Kenwood two-way radio mics. Any tips for strategy to make this work, particularly not requiring more specialized testing equipment, would be very helpful. Also, any warnings and strategies for not damaging equipment would also be helpful. ;-)

[Edit: I've come across this which is basically the opposite of what I'm interested in doing but may give helpful context to someone with more insight that I have. http://www.n1gy.com/headset-adaptor-for-kenwood--baofeng-and-wouxun-hts.html ]

Follow-up:

Works perfectly as described by @JRE below. The 3.5mm pin plugs directly into the breadboard jack on the right; the 2.5mm pin plugs into a 2.5->3.5mm adapter and then plugs into the jack on the left. The wiring specifics should be discernible via the photo.

enter image description here

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  • \$\begingroup\$ @jsotola Sure. I'm intending to breadboard this. \$\endgroup\$ – Aaron Sep 14 at 18:47
  • \$\begingroup\$ Add the schematics inline so that we don't have to follow links and so the question still makes sense when the links die. \$\endgroup\$ – Transistor Sep 14 at 18:47
  • \$\begingroup\$ @Transistor Thanks, I should have done that in the first place. \$\endgroup\$ – Aaron Sep 14 at 19:01
  • \$\begingroup\$ What does it sound like? \$\endgroup\$ – JRE Sep 17 at 21:41
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Let's get a couple of things together here.

First, a diagram of how to connect the Kenwood connector:

enter image description here

That image came from here.

Second is how to connect to an Android phone:

enter image description here

Your throat microphone is most likely a two terminal electret microphone, so Note 2 from the Kenwood diagram should apply and there will not be a 10uF capacitor in the microphone line.

All you should need to do is to connect the microphone line from the headseat to the Android microphone line. Then the microphone ground to the Android ground. The microphone ground is the ground connection on the smaller (2.5mm) plug.

The Android diagram shows where to connect the microphone wires.

Once the microphone is connected and plugged in to your phone, the phone should recognize the headset and switch to headset mode.

That should do it.

Connect the earphone to left or right and ground if you need the earphone.


If you've never used a throat mic before, then you should be ready for a surprise.

Throat mics don't sound like regular microphones. Throat mics pickup pretty much just the vibration from your larynx. All the aspirant sounds ("S" and "Sh" sounds and the like) will be very weak or not present at all. People may have a hard time understanding you.

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