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johnboiles / BaofengUV5R-TRRS

Tiny board that allows you to connect the Baofeng UV5R radio to a smartphone or other device that uses a TRRS connector for audio.
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Why doesn't the speaker output from the phone have to be voltage-divided? #17

Open Tyler-2 opened 2 years ago

Tyler-2 commented 2 years ago

Aren't we sending a lot of power into the handheld's microphone? Seems like this voltage division should happen on both the HT speaker -> phone mic and phone speaker -> HT mic...

Or is the HT mic input meant for this kind of thing?

kronicd commented 2 years ago

Can you advise what sort of voltages you've seen from the HT and from the phone audio out?

I can take a look at this. If the voltage is under 2.2v it is likely ok, but if its approaching or exceeding that, then something should probably be implemented.

I'll look at low component ways to clip at this value reliably, but if voltage in either direction is commonly above it then I'll also take a look at reducing it.