09-05-2016, 12:06 AM
The short answer is check all of the resistors around the eye tube circuit and the 6K7 IF amp tube. How it works is it's looking at the SG voltage on the 6K7. Where you get a strong signal the AVC circuit kick in and drops the gain of the mixer and IF amp this in turn causes the SG volt to increase because of less current flow. This closes the eye. Also have a look at the AVC voltage could be a weak tube or high value resistor. This tube is a bit different than the normal 6E5,6U5, and 6G5 as these a have there own triode driver in the tube.
Terry
Terry
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