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37-650: BREAKTHROUGH!
#1

Finally- something positive to report! Based on my discoveries mentioned in my "Goofed" posting, I replaced the three incorrect capacitors, put it all back together, and, after a little tube swapping, and realignment work, I can now say I do have operations on both SW bands and the entire BC band!

(And literally minutes after I finished aligning the set, my frequency counter arrived, so I can make sure the RF generator is set up correctly...lol... Well, the frequency counter itself needs an overhaul... It must have sat a while: the usual radio issues, minus the mouse... I'll clean her up, and see what she does. )

So, the bands are all reasonably well aligned, I have definite reception, and I will put her back into her cabinet after a few hours run testing. I only had two brand new caps to put in(the third hasn't arrived yet) but I found I had an NOS Sangamo of the right value in stock, and it checked ok, so I put that in for now. I'll swap the other one in when it gives up, if ever.

I adjusted everything by the book, although step 3 for both SW bands was skipped: I have never mastered that one. Once I had BC working correctly, I tweaked the highest and lowest stations into proper position, and all the rest fell into place.

Thanks, everybody, for all the help!
Scott

Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
#2

When you mentioned the incorrect caps in the RF section, I figured that was the problem, and I'm glad you caught it. I'll bet it's a real sense of relief, isn't it? Icon_biggrin

Scott, we're all very happy for you getting this one narrowed down and running again. It might have been a little painful along the way, but it's experience you can't buy that you'll use in future projects.

My 37-650 was my "mistake" radio as well, being my first transformer set/first wood set/first SW set/first console. Looking back, there's been several others I've worked on that would have been better suited for the purpose, but what is, is (so to speak). When it's all aligned and working properly, it can't be beat.

Nice going, Scott!

Bill

Sent from my Pentium II on the AT&T Dial Network




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