another zenith combo

[DaveWM]

after replacing the color amp tube/sound IF (both 6kT8's) and the 6Z10 audio out, the color and audio are MUCH better. Seems the more I run it the better it gets.

there is still some horz lin issues, and I need to check the cathode current (not that there is anything to adj, no eff coil on this one). My guess is a new HOT/Damper/horz osc will clear that up.

the color and tint pots are very dirty so I will most likey be pulling the chassis just to clean up those. While out I will clean on the tube socket pins, and check for out of spec parts. Its kind of a toss up as to should they be replaced, that is the set is working do I mess with it until its not...

the stereo pots are dirty, and I prob should at least replace the output caps (big 500uf 50v that drive the speakers) the AM is iffy, I am pretty sure it has some shorting plates in the VC.

[DaveWM]

well for practice I got the BK 417 setup and did a sweep on a working set, the IF curve looked a bit off, curve at the 42.67mhz was low, so rather than a flat topped with dip at 44 it was more a peak on one side of the 44 and low on the other. But the set works fine so it may just be something I am doing in the setup that is killing the gain in that part of the band.

I used a ungrounded tube shield on the osc tube (B+ pulled to the tuner) and set the AGC bias and RF output to avoid clipping.

I will have to try it on a couple other sets to see if the curve is any different.

Kinda good to do this now and then if for no other reason just to practice.

[DaveWM]

while reviewing some case historys on this chassis, mention was made of poor ground connection being made at plug that connects the hue/color pots to the chassis. too much green and weak color, both of which this chassis exhibits, so I will be pulling that plug to inspect. The only thing is EVERY zenith that I have touched that had that plug was stuck and a major pita getting it loose.