11-28-2010, 04:46 PM
Thanks, Ron
I appreciate your help with these kinds of things. While I'm at it, I have another question about the twin 370 pfd caps in the push button assembly. As you know, the cap itself is a rather strange affair, physically, but electronically appears to be pretty straight forward. I noticed, last night, that after an hour or so of listening the push buttons had all drifted and had to be re-adjusted for optimum operation. As a result, I decided to replace them with a couple silver mica units, hoping to stabilize the situation. The replacements didn't work at all, so I returned the set to it's original configuration. Strangely enough, the original cap configuration then failed to work.
I started taking some voltages measurements, and was surprised when the receiver snapped into normal operation the first time I touched the B+ line with my probe. A small spark when I made contact. The unit is working great, now, with the exception that I am hearing what sounds like very brief, instantaneous, bit of static, every now and then, that also interrupts the signal. Other radios in the house aren't affected this way, so You can assume that the problem is restricted this receiver. All electrolytics have been replaced with appropriate 500v units, and the B+ lines all appear to be firmly soldered. No changes when all tubes are tapped sharply and wiggled in their sockets. Any ideas?
Henry
I appreciate your help with these kinds of things. While I'm at it, I have another question about the twin 370 pfd caps in the push button assembly. As you know, the cap itself is a rather strange affair, physically, but electronically appears to be pretty straight forward. I noticed, last night, that after an hour or so of listening the push buttons had all drifted and had to be re-adjusted for optimum operation. As a result, I decided to replace them with a couple silver mica units, hoping to stabilize the situation. The replacements didn't work at all, so I returned the set to it's original configuration. Strangely enough, the original cap configuration then failed to work.
I started taking some voltages measurements, and was surprised when the receiver snapped into normal operation the first time I touched the B+ line with my probe. A small spark when I made contact. The unit is working great, now, with the exception that I am hearing what sounds like very brief, instantaneous, bit of static, every now and then, that also interrupts the signal. Other radios in the house aren't affected this way, so You can assume that the problem is restricted this receiver. All electrolytics have been replaced with appropriate 500v units, and the B+ lines all appear to be firmly soldered. No changes when all tubes are tapped sharply and wiggled in their sockets. Any ideas?
Henry
