More progress to report!
Late last night, I finished replacing the last electrolytic caps in the power supply. I was only able to restuff the cap that has a paper cover though (C1 in Sams), since the replacement caps I bought (Illinois brand) were too large to fit inside the metal can of the multisection ones. That's probably because they didn't have exact replacement values available at Antique Electronics Supply, so everything that went in was double original capacity.
That being the case, I populated the remaining caps close to their respective circuits. I was able to use spare terminal board points in most cases, it almost looks like they belong where I put them. Naturally, I left the original caps in place on the chassis for the sake of appearances. I also found the AGC pot ground had worked loose, so I soldered it back down.
Today that led to a nice afternoon of slight tweaks, and a good 30 minute session of Fox News and a bowl of ice cream treat myself.
It was short lived, however.
After I shut the set down, I looked over the chassis to make sure none of the work I had done caused any problems. I saw nothing out of the ordinary, but I did smell something odd. Immediately I suspected a hot flyback (smelly old wax), so I popped the HV cage off. Sure enough, melted wax was all over the place and the HV coil had started to sag downward. Right now what I'm going to do is clean up the fly, and replace the silicone since it's old and nasty. Once that's done setting, I will check the horizontal output tube's cathode current to make sure it's OK.
Sams gives a nominal value for the 6DQ5's cathode measurement as 160ma, if it's high I need some suggestions on what to check. Right now I don't think the flyback is bad (it's a low hour set), but I will replace it if I have to.
07-16-2010, 04:29 PM
Hybrid Mode
