[uncleputz]

This chassis is somewhat covered in Sams 591, which I have. The exact schematic may exist in factory documentation, but I don't have access to that. I have the Sams, and a 1077B Analyzer, the usual meters, but no scope. I am beyond a novice at TV repair and am TERRIFIED of high voltage. I collect Magnavox console stereos, models with P-P audio and I have six. From a Concert Grand, down to the cheapest model. The Stereo Theater is third from the top in the lineup both in livery and in price. My Stereo Theater has a TV chassis that I am trying to get sorted.

I have a good raster with full deflection. The 27ZP4 CRT does not test the best, but it may be 30 years since it was turned on. Cutoff is iffy, it flunks the life test. I think it is fair to say the CRT is a bit soft, but, hopefully, it will produce a picture. The goal is to be able to watch the Lawrence Welk show on PBS, over the air, one time, then after that I don't really care if it works or not. And I will have learned something and will have done the work myself. But I need a bit of guidance if someone would be good enough to lend a hand.

I have a good raster, good brightness, but no video and no audio, no "hash" on the screen. I suspect the tuner, but removing it is a horror show due to the remote control setup. Sams suggests checking V1, V2, V3 and V4, which are tubes in the IF strip and audio IF. Plus X1, which is the video detector, a 1N60. I think the video detector diode is in a can that looks like an IF can. How do I check that part? Plus, I have read that the horizontal phase detector diode is a problematic part, so I want to check and replace it (them?) while I have the chassis out. I have test sockets so I can check voltages and will check voltages in the IF strip. Removing the tuner requires removing the safety glass and mask to access a screw on the remote channel indicator. The tuner itself is buried behind the radio tuner. I want to cover all my bases without having to discharge high voltage. I am not sure how to do that, and would be too chicken to try. I don't have a high voltage probe. Sams does not say which part I need to replace the horizontal phase detector diodes. Any suggestions?

So here we are, a novice scared of high voltage working with a TV chassis. It may take a while, but I'll get it eventually. If someone would be good enough to fill in the blanks, I'd really appreciate it.