Get Capacitor Microphone working with Flex-6600`

KI5LST

I have a (most likely cheap) "capacitor" microphone that I'd like to hook to my Flex-6600. It has the three-contact XLR socket. I purchased an XLR to 1.8" TRS, and can attach the microphone to the radio.

However, I cannot get any "valid" audio to the radio. I'm pretty sure the microphone needs bias voltage. When I purchased the microphone, it came with the 7-pin DIN for ICOM radios, which I know provide 5V bias.

If the 3V that the Flex provides isn't sufficient, how do I get more into the circuit? Just pass the mic (+) through a 5V power supply?

As you can tell, I know very little about the "dynamics" of microphones.

For details:
Microphone: Costway EP22260
Frequency response: 20Hz - 20kHz
Sensitivity: 45dB + dB <== doesn't make sense to me
Output impedance: 150 + 30% (1kHz at)
Load impedance: 1000 ohms
Equivalent noise level: 16dBA
Current consumption: 3mA

This appears to be the microphone: https://comstrom.com/products/professional-audio-condenser-microphone-wshock-mount-ep22260-by-cw

TIA,
Joe
KI5LST

AA1SS

Just go into Smart SDR and turn on mic bias. There is also a boost feature if you need more gain

KI5LST

Sorry. Should have mentioned that I tried that. I've tried all combinations of bias and +20dB. No joy.

Geoff AB6BT

Just a suggestion, is the XLR to 1.8" TRS adapter wired correctly?

KI5LST

As far as I can tell, it is wired correctly. I purchased it from Sweetwater. I also ohmed it out, if I remember correctly.

If I crank up the gain in the Audio Control panel (and, yes, MIC is selected), I can get some meter movement, but it doesn't correlate with me whistling in the microphone - so I expect it is all noise.

KI5LST

Oh, pooh. I noticed the XLR connector on the cable wasn't tight, but didn't do anything about it. I just tightened it up, and now it works. Doh!

Thanks for all the suggestions.

Geoff AB6BT

Glad you got it to work.

I'm just curious, what do you mean by the "XLR connector on the cable wasn't tight"

KI5LST

The XLR connector has a sleeve and the center (with the pin sockets). The **** holding the two together wasn't tight.

Joe
KI5LST

Geoff AB6BT

Thanks for the explanation. I'm not sure how that would affect the electrical connection as the shell and insert are usually not connected to anything.

In any case, I'm glad it works.

KI5LST

My guess is that with them not firmly joined, that the pins weren't engaging with the sockets correctly.

73's
Joe
KI5LST

Neil D Friedman N3DF

Just out of curiosity, why not use the 1/4 inch TRS balanced audio input? It’s a feature of the 6600 series that the 6400 series doesn’t offer.

Geoff AB6BT

Per the hardware Manual: