[hpsdr] Penelope MIC input

[Ramakrishnan Muthukrishnan]

I checked if the bias voltage is coming at the mic pin when I transmit 
but I don't get anything at all. The bias is coming from the AIC23B chip 
via a 3.3k resistor. If I measure the DC voltage across the mic while 
transmitting, I see nothing. So, may be more debugging to be done around 
AIC23B.

73
Ram VU3RDD

On 29/01/2022 14:58, Ramakrishnan Muthukrishnan wrote:
> ***** High Performance Software Defined Radio Discussion List *****
> 
> Hello HPSDR Hackers,
> 
> I have been using HPSDR (Merc/Penny/Metis ..) for a while now and since I did not have a good mic, so far I have been using microphone via PC sound card/VAC. For some reasons (most likely some windows update), the mic stopped working a few months ago and since I was more interested in CW and digital modes, I did not bother much.
> 
> I recently got a collar mic online and since it didn't come with any documentation, I tried all +v/AUD jumper combinations (ie. with and without bias, tip or ring). No luck! It didn't work, no output on transmit. PowerSDR doesn't show anything while transmitting.
> 
> Today, I got hold of an electret mic from my junk box and wired it to be given bias on the ring, no ptt (use space bar with PowerSDR), nothing connected to tip, PTT/mic common connected to sleeve. Again no luck. The PowerSDR is configured to take mic input (there are two possibilities in powersdr, mic or linein, I chose mic). I left the default min/max gain etc as it is. VAC is not enabled. Is there any other settings to be taken care of?
> 
> Next I will check if bias is coming on the mic when ptt (space bar) is pressed. Could it be that the AIC23B chip has an issue? Has anyone else faced similar issues? Is there any other PowerSDR setting I need to take care of? I could not find anything relevant..
> 
> Thanks