Ok boys..I just recapped this unit and the multiplex is dead on and I peaked the Ifs..The tuner works well but the dial pointer is off freq by 5mhz..This is not an electrical issue and it no doubt existed since new because the dial pointer itself sits past 87mhz all the way to the left and when you go to the right,the pointer is way past 108mhz..I have aligned quite a few FM tuners and Shortwave radios and I could always compensate with the trimmers if it was off by a couple mhz in the case of FM broadcast..I don't want to do that here..I know the tuner is in perfect alignment but I need a way to move the pointer without ruining the string..Is there a way to get that glue off safely?
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I got it..What I did was chip the glue off.
Alcohol would have worked as well but I put some goop back on to hold it in place once I set the pointer.
Anyway,the biggest I had was aligning the MPX..I kept confusing the 38kc separation coil which you adjust for max deflection and the 38kc trap coil which you adjust for minimum deflection. I changed 6 out of spec resistors in the tuner along with recapping the unit and I ended up with 2.3uv sensitivity and 38db separation which is good enough.I would love to know what the factory spec was for the tuner but I don't think it was any better..It does perform exceptionally well for an old tube tuner.
Alcohol would have worked as well but I put some goop back on to hold it in place once I set the pointer.
Anyway,the biggest I had was aligning the MPX..I kept confusing the 38kc separation coil which you adjust for max deflection and the 38kc trap coil which you adjust for minimum deflection. I changed 6 out of spec resistors in the tuner along with recapping the unit and I ended up with 2.3uv sensitivity and 38db separation which is good enough.I would love to know what the factory spec was for the tuner but I don't think it was any better..It does perform exceptionally well for an old tube tuner.
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good result. Glue that goes brittle has its advantages - Status
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