Quick Question about a Schematic.. - Printable Version
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RE: Quick Question about a Schematic.. - morzh - 01-28-2014
So.....where the other plate powers that were supposed to be connected to it were connected?
In short, what I am trying to understand, have you asked yourself and answered these questions? Is everything connected according to the schematic now?
RE: Quick Question about a Schematic.. - Jamie - 01-28-2014
Your question about what was powering the tubes, it made me look further. Remember when I said that nothing is connecting resistor #55 to the cap? .. Well, one of those three wires I mentioned (from resistor #55), it runs to the RF, but then another wire was connected from that point to the other #67 cap (call it wire #2). Basically the problem was, everything was hooked up to one single 8mfd cap. That's where the hum was coming from! I removed the wire I installed, and moved the wire #2 to the other #67 cap. All is fine.
This radio had been worked on before I got it. The Electrolytic Caps were replaced sometime back in 1945 (from the looks of it). I just replaced parts, so I don't know if I made the wiring mistake or if I just copied it. I recapped this radio back in the summer. It was one of the first radios I ever repaired, so it could have been my fault. I put it aside because it hummed. It has not been used since.
Anyways, the problem is fixed, and a huge thanks to everyone who helped me, especially Morzh!. I learned more everyday.
RE: Quick Question about a Schematic.. - morzh - 01-28-2014
If you look at the sch with one #67 being at the top (or at the right most) and another being inside (closer to the 80 tube) - if all was connected to the top cap it would hum as this is the "unfiltered" voltage; the filtered one (by the field coil) goes to the one close to the 80 tube and this is where all those RF power and #55 resistors should've gone to.
Anyway, all is well that ends well.
Good job!
RE: Quick Question about a Schematic.. - Jamie - 01-28-2014
You know, I had gone over that schematic 100 times and I couldn't see the error. I swear, I spent hours looking at this radio. Now that I found it, I don't know how I ever missed it. Sometimes it's like unraveling spaghetti. I think I am getting better, but I don't know. Thanks a million Morzh!