By any chance, do we have any other ham radio operators here?
On a quest to transmit nicer audio out of my Kenwood TH-D74A, at least for analog FM simplex work, I've been trying various cheap things intended for the
ham radio market.
1. The radio's internal mic: I like this the best so far.
2. Kenwood Speaker Mic: too peaky in the highs... harsh.
3. Heil headset: cheap, about $25, probably nothing at all like Heil's other products. Extreme breath noise when close to the mouth, even though it has
some foam covering the mic element... very poor pick up once it's more than a couple inches away from my mouth.
Example wav:
https://www.sendspace.com/pro/dl/3pmb01Contents:
* keying up a repeater that makes a strange sound as a fan or something spins up??
Then, me on internal mic (echoed back by D-Star)
Then me on speaker mic (plus echoed back)
And finally, me on the cheap Heil headset (echoed back)
I have no idea what sort of level or impedance the input on the radio expects, but it does receive audio via a 3.5" jack.
Would something like a Sony ECMS-907 work, since it's self-powered, has an on/off switch (PTT???), and outputs to 1/8"??
I'm trying to find something with reasonable balance across frequencies from about 150 Hz to about 8kHz or so, and with limited proximity effect and breath
noise.
Or, what circuitry would be needed to take line level off a mic pre/cheap soundcard, and make it suitable for the radio's 1/8" input? Said circuitry would
need to include a switch for PTT.
Open to all ideas if they're not too complex.
73,
Chris
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