Pearce Simpson Bengal SSB Low AM Sensitivity

[Justin B.]

The plot thickens...

I hooked up my VFO and tuned in to Chan 38 and had my wife give me some 10 counts on the Midland. I tweaked in the "crystal" freq until her voice was just right and started listening to 38/LSB on the Bengal and had the Midland in the other end of the shop.

Although the background noise is high (normal?) on sideband the actual signals behaved the same way they on AM! I am starting to wonder if the FET2 3SK22-Y is tired... The voltages look good but it might be starting to break down. I have did a little searching but don't find any of these for sale on this side of the pond.

Anybody know of a good substitute?

73,

 

[Justin B.]

I removed the 3SK22 and the background noise didn't change. I found a source for the them and ordered a few so they should be here in a couple of weeks...

 

[Justin B.]

OK, I'm about at the end of my rope on this one. I got in the new 3SK22 FETs today and popped one in - no change! I believe this radio has had this problem for quite a while and somebody has did extensive troubleshooting. When I went through the IF train I saw signs that several IF cans had been removed, probably for testing, and other traces.

So, it remains mostly deaf only receiving very strong signals and when I key up my walkie I only get about an S3 indication instead of over S9.

I guess this will go on the "maybe someday" shelf. Maybe if I live long enough I'll get back to it someday...

Thanks for the help!

73,

 

[doffo]

It was worth a shot. I got an older President Washington 858 chassis radio which took away several hours trying to troubleshoot. I purposely put it up high on a shelf in the garage where I need a ladder to get to it. Keeps it out of reach so I do something else instead of trying to find out the problem it had. I did bring back down a Courier Gladiator PLL 23 channel thats been converted into a 40 channel. I think after all this time it had a bad Audio chip? I need to wire up a mic and then I can begin my luck to trying to repair it.

I did buy one a couple years ago for around $80 on eBay, an actual 40 channel one. Felt like it was a great deal.

 

[brandon7861]

It's been very hard to work on this with a copy of a Sams as the pictures are not very easy to determine where the components are actually at. I may need to break down and see what manualman.com has for this...

There is a normal schematic on CBTricks and a block diagram in the owner's manual.