[aprssig] Mic-E and HTs
scott at opentrac.org
Tue Dec 13 15:10:49 CST 2005
Ok, now you've got basically what I came up with. Only I wasn't able to get
PTT detection directly from the I/O pin (this was with a Motorola GP68
handheld, don't remember the troubleshooting sequence exactly) so I added a
The only problem I've encountered with this setup is that the audio is lower
than I'd like. Larger values for the capacitor help, but I think I'm still
going to have to add an op amp or transistor there.
But my question remains - has this always been the accepted way of doing it?
Why isn't there any documentation out there about it?
----- Original Message -----
From: "Robert Bruninga" <bruninga at usna.edu>
To: <wa8lmf2 at aol.com>; <aprssig at lists.tapr.org>
Sent: Tuesday, December 13, 2005 12:59 PM
Subject: Re: [aprssig] Mic-E and HTs
>>> wa8lmf2 at aol.com 12/13/05 1:37 PM >>>
>bruninga at usna.edu wrote:
>>Ill draw it...
>I don't see how the second half of your diagram
>(the part labled "Combined PTT" could possibly work.
> You show one side of the mic element grounded all
>the time with PTT button then grounding the other
>side, thereby shorting out the audio.
Argh, your right. I was too quick to draw that.
I fixed it now with the typical 2.2k resistor...
Stephen H. Smith wa8lmf (at) aol.com
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