04-03-2013, 05:13 PM
[Hope I have posted this in the proper place]
I am restoring the chassis on this radio and have replaced all caps (except micas for now), and most all resistors. Those I have not replaced were well within spec.
I aligned the IF with no issues, however I am not able to hear the fundamental at 1500kcs or 550kcs from my signal generator no matter where I adjust 16 and 17. I have heard, what I think is a harmonic, and if I spot it on 1500kcs, I hear no stations in the BC band. However, I can detune 16 and hear BC stations, but they are very broad, like 100kcs+, so something is obviously amiss.
Assuming everything else is correct, Osc transformer (checked), etc., what should I be looking for. Only mica cap I've found way off is 4, which reads about 105pf and should be about 250pf. Currently don't have one to replace it with. I have also checked all the IF transformers and found them to be right in spec., no open windings, etc.
Another odd thing was a wire installed on the antenna coil wrapped at both ends connected to, I think, 7 and 5 taps. I am assuming it was a "gimick cap" for something. I removed it, however not knowing what it was for, should I replace it? At first I thought it was not original, but I read somewhere else that someone else found this in his 41-296. Photo attached.
Any suggestions would be greatly appreciated. I am not an expert tech by any means, so forgive me if I've left out any important points.
Thanks
Brian
I am restoring the chassis on this radio and have replaced all caps (except micas for now), and most all resistors. Those I have not replaced were well within spec.
I aligned the IF with no issues, however I am not able to hear the fundamental at 1500kcs or 550kcs from my signal generator no matter where I adjust 16 and 17. I have heard, what I think is a harmonic, and if I spot it on 1500kcs, I hear no stations in the BC band. However, I can detune 16 and hear BC stations, but they are very broad, like 100kcs+, so something is obviously amiss.
Assuming everything else is correct, Osc transformer (checked), etc., what should I be looking for. Only mica cap I've found way off is 4, which reads about 105pf and should be about 250pf. Currently don't have one to replace it with. I have also checked all the IF transformers and found them to be right in spec., no open windings, etc.
Another odd thing was a wire installed on the antenna coil wrapped at both ends connected to, I think, 7 and 5 taps. I am assuming it was a "gimick cap" for something. I removed it, however not knowing what it was for, should I replace it? At first I thought it was not original, but I read somewhere else that someone else found this in his 41-296. Photo attached.
Any suggestions would be greatly appreciated. I am not an expert tech by any means, so forgive me if I've left out any important points.
Thanks
Brian