[Elecraft] Electret microphone wiring

[Ramiro Aceves]

Tom W8JI escribió:
> <<<<I am trying to use a cheap computer microphone in my K3, front 8 pin
> connector. I have some doubts that I would like to solve before making a
> mistake:
> 
> 1- Can I use pin 1 directly atached to the electret capsule and set bias
> in config:MIC SEL? Or should I use also some kind of resistor/condenser
> arrangement to the 8V DC pin6?
> 2- For GND: shoul I use pin 7, pin 8 or both pins?>>>>
> 
> 
> I just went through that. My Sennheiser headset now works fine using 
> internal settings for bias.
> 
> Pin  7 and 8 are the same connection point. I do not believe it is best 
> that they are the same, in my unprofessional opinion one should be a 
> shield ground and one an audio ground, but they are the same.

Oh yes, thanks for your help. I have mine working now. I have to get 
optimal gain and compression adjustments, but the microphone works great 
at first glance.

> 
> I had to modify my audio input grounding to cure RFI. My headset has a 
> long cord, and when I would stretch the cord I would get bad RFI with my 
> yagi stacks pointed back at my house. Elecraft has a mod for this, but I 
> changed more. I soldered the wire around the mic connector shell to the 
> connector shell, and I grounded the circuit board pin 7 and 8 via a 
> copper foil that grounds under the cabinet screw in that corner.
> 
> Now I absolutely no RFI into the audio no matter what I do, and with the 
> very long cord all stretched out like an antenna! The Elecraft mod was 
> an improvement, but the copper foil was a total cure for me.

Thank for the information Tom. If I get some RF problems I will do that.

Thank you.

73, EA4NZ, (ex EA1ABZ)


> 
> 73 Tom
> 
> 
> 
>