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<DIV><SPAN class=950235000-07022006><FONT face=Tahoma size=2>One of the
digipeaters I upgraded to UIDIGI last summer had a small circuit card mounted in
the TNC. I didn't pay much attention at the time, but it turns out to be a small
reset circuit for the TNC. Basically, it listens on the audio input for a
specific tone for 2 seconds, at which point it trips the reset line of the TNC.
It's used to recover from a severe lockup of the TNC (which it turns out UIDIGI
sometimes suffers from). I had to use it once recently and it saved me from a
miserable hike up a snow-covered mountain.</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma size=2>I'd like to come up
with something similar for the other digis I maintain. But I haven't yet found
any schematics for anything *simple* that does the trick. I'm hoping maybe
somebody here has some schematics, or a pointer to a site with
some.</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma size=2>Failing that, when
Spring comes I'll hike up the mountain and reverse-engineer what's up there,
though that's not exactly my strong suit.</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma size=2>Emphasis on the
"simple". This one uses a single tone and I seem to recall it had one IC (maybe
two) and only a couple of discreet components. A DTMF decoder would do the trick
(and be less prone to spurious resets, presumably), but I really don't have the
ability to get into PIC-based designs.</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma size=2>Anybody seen
anything like this?</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2>Brad.</FONT></SPAN></DIV>
<DIV><SPAN class=950235000-07022006><FONT face=Tahoma
size=2>VE3BSM</FONT></SPAN></DIV></BODY></HTML>