12-20-2016, 11:00 PM
I have been working on the 90 this week, recapping and replacing out of tolerance resistors. This thing has really been hacked, badly! I have gotten thru the power supply and AF section and speaker. I powered up this evening and after finding a bad detector, got it playing. I am feeling pretty good about that, considering the rewire from all the hacked up previous "repairs" was quite extensive. It will tune in one strong local station right where it should be on the dial. I checked the IF frequency lwith my scope and it appears to be right on 260 kHz. This is the single tube 47 output, and according to Ron's info in the tech section, it should be tuned to 175 kHz. My question is: can it even be tuned to 260 kHz and operate? I am assuming one of the previous repairmen aligned it to 260 in error? I am just wanting to confirm the correct IF before attempting a change. There wouldn't be an odd ball run that is supposed to be tuned to 260, perhaps?
I won't be doing an alignment until i complete the recap on the RF section. Still need to clean up the tuning condenser too. It needs new rubber bushings which won't allow me to tune the full range of the radio.
Thanks for any insites as to what is going on.
I won't be doing an alignment until i complete the recap on the RF section. Still need to clean up the tuning condenser too. It needs new rubber bushings which won't allow me to tune the full range of the radio.
Thanks for any insites as to what is going on.
Chris H
N9WHH