President Jackson squeal

[Ratfink]

Been messing with this radio for a while and when the DK is set any higher than say 1.5 watts it gets a squeal it doesn't do a lot of wattage on Am but SSB it seems to do well. I thought maybe a bad VR or bad final but I am not a great tech.

 

[Ratfink]

I can crank the Dk way up and it quits but when set in a normal range it acts up

 

[sp5it]

Before you'll start breaking your radio how on dummy load?
Mike

 

[Ratfink]

I don't have a DL

 

[sp5it]

Borrow or build one.

 

[Ratfink]

So your telling me I have to have a load to diagnose this radio? My Swr's are 1.0 everything else is good but this radio I'm not a duck by any means I just need pointed in the right direction.

 

[sp5it]

SWR means that your antenna impedance match output impedence of your radio, nothing else.
You have to find what is reason of squeal.
That can be RF floating back to radio on feeder shield. This in most cases can be the reason.
That why I asked you to to connect radio to dummy load to exclude one reason.
Depends on result we can move forward with diagnose of your radio.
2166 can get parasitic oscillations - it is also common failure of Jackson, transmitter part of radio can be mistuned because of radio age, we have to find it.
Mike

 

[sonoma]

the age of the radio there could be some 10 volt caps going bad and can also cause feedback problems. I just recapped my old Jackson last year for odd things going on inside the radio. changed the 10 volt to 25 volts and the radio came back to proper performance.
like ike said there is items you have to eliminate if you want to repair the radio.