09-18-2016, 03:19 PM
(09-13-2016, 08:25 PM)Mike L Wrote: Again, thanks for all the help! I have not adjusted anything yet. I do have a signal generator (Precision E200C) and a VTVM (Heathkit V-7A), but I have never checked or performed an alignment before. I had to order test leads for both pieces of test equipment. when I get to that I'm sure I will have more questions.
I am concerned about the heat generated by resistors #11 and #9. The Spec sheet I have, Riders 3-25 shows that resistor #11 (16k) should be rated at 5 watts. In the link earlier Ron Ramirez's site recommended a 3 Watt. Am I over thinking the heat generated? I'm going to try an actual 3w, 16k and not the parallel setup (see earlier post) I had to see if there is a difference. Is the extra heat on #9 due to the increased resistance? That resistor is rated at 1 watt.
I believe I have been bitten by the bug. I just acquired a model 84, cosmetically in good condition. Next after this one is complete.
Sorry I miss your Q. By increasing the resistance of #9 it lowers the current flow through #11 and increases the screen voltage on the mixer tube. This in turn raises the gain of the mixer a bit. If you can't sleep at night over this hot resistor swap them out for 5 or 10w units. Remember in '32 it was all about the money.
The model 84 is an updated version of the 80. Circuit is very similar but the 36's are re[placed w/77's. Same drill to fix all caps and resistors, good chance that the ant and or osc coils are open. Better sounding set as the spkr is about twice the size of the 80.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry