01-01-2017, 12:55 AM
(12-31-2016, 09:33 AM)Mike L Wrote: Thanks again Terry. It seems to be "functional" although the band calibration is off. I'll address that later. The RF controls were very scratchy, at least RF-1 was. Spray cleaner didn't work so I removed them to open them up for inspection. RF-1 pot is defiantly bad, the other cleaned up but here is the problem. RF-1 is marked with 20000 (assuming 20k) RF-2 is clearly marked and measures as 25,000 ohms. The problem is the schematic shows both of these controls as being 200 ohm! Why would there be such a huge difference. They physically and brand are not the same so it is safe to assume they were replacements. So do I put 200 ohm or 20k ohm pots back in? Both are carbon wiper, but audio or linear taper. How is that determined?
I would go with the values listed on the schematic. You probably want linear tapper. Audio tapper would give you not much level change it the last half of the rotation. Must use carbon not ww pot. WW looks like an inductor to the signal.
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