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Brandon - I pulled the cover off my "good" radio and the collector has around 10V so I put the 1K resistor back in the fubar one. Here's scope grabs from base and collector of fubar and good. First with r315 AT 2k. Fubar Base: Fubar collector: fubar with r315 at 1k Base: Collector...

I upped C313 to 10 uf and wound up with R315 at 2K and got about 6.4V at the collector but no more gain. Something is not right with that map stage or the input is a lot lower than it should be. Maybe I'll post up a couple scope grabs... After all of this messing around I can "yell up" about...

Brandon - I get the following voltages on Q302: E - +1.66V B - +2.28V C - +9.51V The voltages when 2N3904 in circuit are similar. The base and emitter voltages are a bit higher then the print but the difference between them looks correct for a forward biased junction. I found R313 a bit out...

I'll put the original 2SC900 back in and check. Seems I remember base and emitter voltages looked reasonable. 73,

I started tracing from the mic amp to the balanced modulator and found that on the collector of Q302 (SSB Mic amp) instead of the 6.93 V I have right at 10V with a very small modulated signal riding on it. I popped out the 2SC900 and tacked in a 2n3904 and have the same results. I'm thinking...

OK, I spoke too soon. After changing out FET2 it was totally deaf so I tried another 3SK22 and it was still totally deaf. I put the original 3SK22 back in and I was again able to "hear" strong signals. I'm suspecting the FETs I ordered were likely counterfeit parts. :-( This makes me think...

I have went through the transmitter alignments and none of the slugs peaked anywhere near the top of the cans. I think this may wind up on the "someday shelf" alongside the Bengal SSB!

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...

I continue going through this neglected radio and I think I have got most of the gremlins exorcised except SSB power. Receive seems fine so I left the synthesizer alignments alone and I went through the transmitter alignments and have about 2.5W dead-key and 5-5.5 W modulated. I have set the...

It is better but still looses some detail in printing but I can pull it up on a monitor and it looks much better so I can do it that way. Thanks for the extra effort!

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...

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...

Dan - Outstanding! I should be able to find stuff on the board, now! Thanks...

Dan - I hate to bug ya but could you re-scan CB-60 pages 80-83 at the highest resolution you are able? Once I blow them up and print I can't make out where things are at! I'm printing at 1200 DPI graphics mode... Thanks,

OK, the AGC is not the culprit and I'm starting to think I have another possessed radio on my hands! The channel 6 loudmouths were coming in pretty good so I kept the radio on that channel and poked around. I found that if I coupled a carrier of the same frequency I was listening to the radio...

You're right. Seems like my first thought turns out to be the hard way to do something! 73,

I've spent most of the day poking and prodding with no luck. I have went through and touched up the IF and RF alignments. I have set the bias on the FET. I have hooked up the signal generator and followed the signal through the IF train and right after the detector. With a stable constant...

Thanks! I'll check the area around TP1 and if I don't see anything obvious I'll re-solder everything in that circuit to be sure. 73,

Man, I hope not - there are a ton of electrolytics on this board! Looking at the schematic there are non in the oscillator circuit but there are in the AM AGC circuit and mixer so maybe I'll do those... 73,

Checked TP1 (TR1 emitter) and just as soon as I clipped on the scope probe the radio woke up and now won't quit! I have about a 4V sine wave riding at about 8V on TP1. When I removed the probe everything still worked even after numerous off/on cycles. We'll see tomorrow if it still lives or...