07-28-2024, 04:34 PM
> For that cap block I used a .01uF Y2 safety cap but as you can see in my first picture the electrolytic cap you are referring to does not exist in my chassis.
Yes I understand that the later versions of the 80 and all of the 81 & 84's don't use that 10mfd cap. But I suspect that it was a cost cutting measure to replace it w/a matching .015mfd cap. What it does is filter the negative leg of the power supply. That's why 10mfd is much better than .015mfd and now days you get them in a small enough size to fit within the block. The voltage rating is low as it's just has the bias voltage across it may be 16v so a 35v cap would be fine.
> As for the gimmick around the wire from the volume control center tap, how tight do the windings need to be or does it not matter?
I don't a 80 chassis apart but I do have a 84. It has 2 turns over about 1 3/4". It's there to coupe some more oscillator signal thru to the antenna to improve strong signal mixing. Remember there is no agc/avc to help control the gain any of the stages.
Yes I understand that the later versions of the 80 and all of the 81 & 84's don't use that 10mfd cap. But I suspect that it was a cost cutting measure to replace it w/a matching .015mfd cap. What it does is filter the negative leg of the power supply. That's why 10mfd is much better than .015mfd and now days you get them in a small enough size to fit within the block. The voltage rating is low as it's just has the bias voltage across it may be 16v so a 35v cap would be fine.
> As for the gimmick around the wire from the volume control center tap, how tight do the windings need to be or does it not matter?
I don't a 80 chassis apart but I do have a 84. It has 2 turns over about 1 3/4". It's there to coupe some more oscillator signal thru to the antenna to improve strong signal mixing. Remember there is no agc/avc to help control the gain any of the stages.
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