President Madison Freq Counter

[575]

Yes, the Galaxy FC-347's and the FC-390's will work fine for your Madison. You have to go in and solder a bridge inside the unit to get 7.8mhz IF, but other than that it's easy to hook up and it will be accurate on all modes.


~Cheers~

What kind of bridge and where?

like this?

 

[nomadradio]

The circuit board found in this type display was updated multiple times. The exact "masonic-lodge handshake" needed to convert it would change with each update. One version requires just one gap between solder pads to be bridged with solder. Another version requires two. I have a vague memory of one version that required three. Shoulda kept better records.

Alas, I have not seen a complete description of all these variations. Each one has a unique circuit-board number that should indentify which one you have. How far you have to tear into it to read this number also varies.

73

 

[575]

The circuit board found in this type display was updated multiple times. The exact "masonic-lodge handshake" needed to convert it would change with each update. One version requires just one gap between solder pads to be bridged with solder. Another version requires two. I have a vague memory of one version that required three. Shoulda kept better records.

Alas, I have not seen a complete description of all these variations. Each one has a unique circuit-board number that should indentify which one you have. How far you have to tear into it to read this number also varies.

73

maybe this has what we are lookin for

http://www.cbtricks.com/radios/galaxy/fc347/index.htm

 

[ExitThirteen]

Yes, that is it. Depending on the Rev level. You have to jump across 1 or 2 sets of "pads" to switch the IF from 10.69(7)5 to 7.8, which is what the Madison uses.



~Cheers~

 

[nomadradio]

Hmm. Never got around to pointing out the built-in 1 kHz error that counter will have on a single-conversion Uniden SSB CB. Only in sideband modes, should read okay in AM.

The plus-or-minus offset this counter applies when either the USB or LSB wires is turned on will be 2.5 kHz for the 10.695 MHz setup that it comes with.

But after you modify it for a radio with a 7.8 MHz IF this offset changes to 1.5 kHz. This is what the Uniden SSB CB models with dual-conversion AM receive will use inside.

The single-conversion radios like a Cobra 142 or a Uniden Washington use a 2.5 kHz offset for sideband, NOT 1.5 like the counter is programmed for.

The counter should adjust okay on AM. If it won't, that's a separate issue. Mike covers that quite well.

But the two sideband modes will show a frequency reading that's 1 kHz wrong on either sideband mode for a single-conversion CB. Put the counter on a Uniden Madison or Cobra 148 and it will read on sideband just like it should.

73

 

[575]

im nervous about hackin up something, so i ordered this

im sure it will be off freq a bit and wont track on receive. however, im only interested in getting close. ssb is by ear anyway!

 

[575]

Welp just as I thought. On freq is at 1 o'clock instead of 12. Close enough. However this thing doesn't read ssb. It's already back in the box and Amazon return slip printed. Guess I'll balls up and hack the 347.