I test drove a mod I found by Bill Cheek to add a signal meter to various radio shack scanners, specifically the 2006. It was pretty simple and its really cool to see the needle bouncing, and it got me thinking about adding this to other radios. I was thinking of taking a shot at adding one to a Pro 197, but in looking over the schematics I got a little lost on where one might tap into the IF circuitry to accomplish this, if its even feasible on this radio. Has anyone does this before? If its possible, where does one tap the signal at?
Pro 197 with Bill Cheek signal meter mod?
- Thread starter hanlonmi06
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slicerwizard
Member
You could try poking around with a DC voltmeter. Best if you were tuned to something like an FRS channel and keyed/unkeyed a radio.
Thanks for the reply, however that's precisely what I want to avoid doing inside the radio if possible.
I'm hoping to properly tap the IF stages as described in his modification notes.
I'm hoping to properly tap the IF stages as described in his modification notes.
PRO-2006 "S" meter output
Parts : 10Kohm 1/8w resistor, 0.1 uf capacitor
Locate D33 on the linear PCB. Solder in the 10K resistor to the ANODE
of this diode. Note this is not the same as TP2. Connect a wire from
the free end of this resistor to a rear panel jack (RCA). Solder the
0.1uf capacitor from the jack's center terminal to ground. Output on
this jack follows the AGC voltage. Negative for no signal, goes
positive when a signal is present, increasing with signal strength.
A 1Volt full scale panel meter makes a good "S" meter
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Much more detailed information with ascii schematic
[source]
www.wentztech.com
Parts : 10Kohm 1/8w resistor, 0.1 uf capacitor
Locate D33 on the linear PCB. Solder in the 10K resistor to the ANODE
of this diode. Note this is not the same as TP2. Connect a wire from
the free end of this resistor to a rear panel jack (RCA). Solder the
0.1uf capacitor from the jack's center terminal to ground. Output on
this jack follows the AGC voltage. Negative for no signal, goes
positive when a signal is present, increasing with signal strength.
A 1Volt full scale panel meter makes a good "S" meter
--------
Much more detailed information with ascii schematic
[source]
_Pro 2006 Mods | KB9JJA
Paco-Jerte
You Member, Member!
Nice 411. I will keep it in mind if I bump into a 197. Still have my 2006 with LED mods
iMonitor, are your instructions about the 10K resister at the Anode of D33 for the 197? I wanted to just clarify since the Pro 2006 mod utilized the same diode number.
Those are not my instructions. I posted a link to the source at the bottom of my post.
_Pro 2006 Mods | KB9JJA
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