Hi - I started on a re-birth of a 1969 Zenith color console. I got it from a guy who got it from an abandoned house after sitting for many years. This was a nice console in its day, the flagship model… It is a Z6547W with a 16Z7C50Z chassis. Needless to say, the set is beat. The HV was clearly arcing until the set gave it up. A bunch of destroyed parts and tubes. I did a lot of work trying to get it going but the high voltage is the issue at this point. The flyback is in bad shape but still has continuity in the windings. Don’t know if it arcs internally under load however it is clear that there was HV arcing in the filament winding so I have ordered some new 30KVDC wire. I was going to replace the two capacitors on this flyback assembly and the focus rectifier. I think the 150pf cap was the source of arcing to ground in another place as there are literally cracks in the cap. It made the focus rectifier light up while it was self destructing.

Aside from that, I was thinking of replacing the entire flyback. I can’t find a NOS that is the right one but I have a very nice Thord FLY 323 that I was hoping to retrofit into this chassis. Here is the conflict though…

The flyback I have is a direct replacement of the Zenith chassis of the “X” year - 1967. The following year or two, Zenith added a horizontal efficiency circuit so they made some changes to the flyback by adding a different tap off the doughnut and adding a few more components that feed the efficiency circuit directly. I have studied the schematics for a few days and I think this can be made to work if I move a few connection points around and add a few new parts (22pf cap, 68K and 47K resistors).

Has anyone done this before? I thought I would ask in case the answer it “don’t do it!”

I have attached two pics of the schematics of the horizontal output transformers. The first is the correct 1969 flyback and the second is the older 1967 NOS that I hope to fit into the first.

Any thoughts would be appreciated!!

Dave

Better pictures of the schematics!