[FoxHunt] HTX-202 Audio S-Meter Mod

[R. Simmons]

It's all there on the website... all the principles involved. The S-meter
signal is fed back to the DF unit through the center conductor of the
antenna co-ax...

----- Original Message -----
From: "Jess Hancock" <jhancock@cwv.net>
To: <foxhunt@mailman.qth.net>
Sent: Thursday, June 06, 2002 1:51 PM
Subject: Re: [FoxHunt] HTX-202 Audio S-Meter Mod


> How do you bring out the S-meter voltage?  Did you use an existing
> connector, add one or what?  What signal processing did you use between
the
> tap off point and the polar plotter?  Marv said he didn't see any details
on
> your web site.
>
> Thanks, Jess, w4pqk
>
> -----Original Message-----
> From: R. Simmons <pelican2@silcom.com>
> To: foxhunt@mailman.qth.net <foxhunt@mailman.qth.net>
> Date: Thursday, June 06, 2002 4:06 PM
> Subject: Re: [FoxHunt] HTX-202 Audio S-Meter Mod
>
>
> >Quite right, I use the signal on pin 13 of the MC3372 chip... the pdf
data
> >sheet shows a graph of the signal on this pin vs RF input signal.
> >
> > As Marv says, I use it to drive a feedback loop in a polar plot display
DF
> >:
> >
> >www.silcom.com/~pelican2
> >
> >And it works nicely...
> >
> >----- Original Message -----
> >From: "Jess Hancock" <jhancock@cwv.net>
> >To: <foxhunt@mailman.qth.net>
> >Sent: Thursday, June 06, 2002 9:41 AM
> >Subject: Re: [FoxHunt] HTX-202 Audio S-Meter Mod
> >
> >
> >> IC4 is a Motorola mc3372 IF strip.  Check the link:
> >>
> >> http://pubpages.unh.edu/~aperkins/pdf/mc3372.pdf
> >>
> >> Pin 13 is labeled Meter Drive and in one of the diagrams is labeled
RSSI
> >> Output which I believe is the S-Meter output of the chip.  In the HT
> >> schematic this is connected back to pin 10, Filter Input.  Filter
output,
> >> pin 11 appears to be DC coupled and drives a line labeled SGL.  The
> >junction
> >> of R33 and R34 might be a possible S-meter dc voltage pickoff point.
> >>
> >> Let me know.
> >>
> >> 73, Jess, w4pqk
> >>
> >>
> >> -----Original Message-----
> >> From: Marvin Johnston <marvin@rain.org>
> >> To: foxhunt@mailman.qth.net <foxhunt@mailman.qth.net>
> >> Date: Thursday, June 06, 2002 11:34 AM
> >> Subject: Re: [FoxHunt] HTX-202 Audio S-Meter Mod
> >>
> >>
> >> >
> >> >Bob Simmons, WB6EYV, taps into the HTX-202 S meter circuit to use the
> >> >HTX-202 with his Yagi Plot setup. I checked his website
> >> >(http://www.silcom.com/~pelican2/) but didn't see any mention of the
> >> >mods. He does read this list, and can probably answer the question.
> >> >
> >> >Marvin, KE6HTS
> >> >
> >> >Dennis Boone wrote:
> >> >>
> >> >> As an electronic technician, I'm not a bad computer sysadmin, but I
> >> >> went looking for such a point a few years ago for exactly the same
> >> >> reason.  My fuzzy memory seems to recall that the only place s-meter
> >> >> intelligence was available outside of an IC was in a form suitable
for
> >> >> driving a display, e.g. bcd, serial, or some such.  I'd love to be
> >> >> proven incompetent on this one, though.
> >> >>
> >> >> Dennis Boone
> >> >> KB8ZQZ
> >> >>
> >> >>  > I know a ham that claims to have done most of the factory service
> >work
> >> >>  > on the 202 for RS.  I posed the same question him a few years ago
> >and
> >> he
> >> >>  > could not come up with a point.  He seemed to be sincere  but you
> >> never
> >> >>  > know.  The tight front end would make it a great fox hunting rig.
> >> >>  > Please post the information if you find a mod.
> >> >>
> >> >>  >  > Has anyone ever tried to find a point on the Radio Shack
> >> >>  >  > HTX-202 HT PCB to tap off the voltage/signal from the
> >> >>  >  > S-meter display circuit chain?  I'd like to see if I can add
> >> >>  >  > a voltage driven osc for a audio S-meter to a -202.
> >> >> _______________________________________________
> >> >> FoxHunt mailing list
> >> >> FoxHunt@mailman.qth.net
> >> >> http://mailman.qth.net/mailman/listinfo/foxhunt
> >> >_______________________________________________
> >> >FoxHunt mailing list
> >> >FoxHunt@mailman.qth.net
> >> >http://mailman.qth.net/mailman/listinfo/foxhunt
> >> >
> >>
> >> _______________________________________________
> >> FoxHunt mailing list
> >> FoxHunt@mailman.qth.net
> >> http://mailman.qth.net/mailman/listinfo/foxhunt
> >>
> >
> >_______________________________________________
> >FoxHunt mailing list
> >FoxHunt@mailman.qth.net
> >http://mailman.qth.net/mailman/listinfo/foxhunt
> >
>
> _______________________________________________
> FoxHunt mailing list
> FoxHunt@mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/foxhunt
>