President Washington

[Lakes_Region_Comms]

Hello everyone! I have a President Washington Base station, and it is acting weird, when I press the PTT on the mic, it transmits, but no audio, I’ve switched the mic about 3-4 times and still the same thing, I’ve tried different antennas, and still the same thing, I believe it might be the finals of the radio, Any ideas on what could be wrong?
Edit: Forgot to add, it DOES have the extra channel modifications, and I have the switches on the correct mode for regular CB 40 channels

 

[rcarl]

Start by getting it recapped. Its 42yrs old.

 

[AB5ID]

Do you have a normal carrier on AM? What does it do on SSB? Have you tried another microphone?

 

[tramd]

If it has RF power out, (the RF meter on the radio goes up to around 3- 4 watts), then the RF driver transistor and RF final transistor (only one final as it's a cb radio) are okay. On SSB is there modulation? You should see the meter swinging as you talk. If you put it in PA mode with a speaker or headphones plugged in, do you hear anything? If not, you have an issue with the audio circuit. Like rcarl said, if it hasn't been recapped, that may be the problem. Electrolytic caps weren't made to last 40 years. I have repaired many older radios in the last few years that after recapping them they worked fine. Just needed an alignment afterwards, is all. If that is the early President radio with the 858PLL with the two buttons on the right lower side and not three, they have a tantalum cap C179 that causes trouble. They short out, and the radio usually just doesn't work right and SSB won't work at all. This doesn't sound like your issue though.

 

[Lakes_Region_Comms]

Do you have a normal carrier on AM? What does it do on SSB? Have you tried another microphone?

I’ve switched the mic about 3-4 times and still the same thing

Yes, I’ve changed the mic multiple times, and yes it is in AM mod

 

[AB5ID]

Do you have normal power out on SSB? Is your received normal?

 

[spongella]

Excellent responses so far. I had one of these radios years ago, liked it very much.

Just some fundamental questions....

Do you get a meter swing when you switch to SSB? I think someone asked that question already but I don't think you answered it.

You mentioned trying different microphones and they did not work, but that could be due to incorrect wiring of the microphones.

I would open up the original microphone that worked and check for problems like broken/ pinched wires. Then check the microphone connector to be sure there are no broken wires.

I would also open up the radio and check the Mike Gain pot. If possible, spray it with DeOxit, as it might be dirty. In my experience older radios that were from a smoker can have problematic variable pots.

Hope this helps and keep us posted.

 

[ind224]

The audio chip in a real (4 pin mic 2 button panel) President Washington are suspect. Probably easier to find never used 6LQ6's.