John Williams wrote:

Group,

I need an expert opinion on a Swan power supply.
I have a 350c and 117xc. The transceiver has problems I will deal with
later. For now, without any test gear, I want to rule out power supply
because I'm putting it on ebay. The rig I'll have to sell seperately to a
swan tech. on a reflector like this.

The radio has a consistant loud "CRACKLE" noise on receive. ( there is No 60
cycle hum.) All bands, all volume levels, all rf gain levels, with/without
antenna. crackle noise is steady. Without need to warm up.


If the volume control varied it, I would have suggested bad
caps in the IF transformers. See my page
http://www.geocities.com/wa2ise/radios/repair.htm
about half way down.

I'm not familar with this radio, it's a tube set, yes?
If so, try pulling the audio output tube. Still crackle?
Put the tube back and pull the audio driver (probably a
triode like a 6AV6). If you can get silence doing this,
then the problem exists somewhere closer to the front end.