...

If its the same chassis ## it probably is the same.
This is when they were changing the chassis numbering scheme
from tube count to screen size for the first numbers.
Most Zenith FBT's start with an S-##### & are
marked EIA 343 so Zenith made. They are not a quick
swap so be sure first.
I bet someone has the factory manuals & can check for you.

73 Zeno:smoke:

If its the same chassis ## it probably is the same.
This is when they were changing the chassis numbering scheme
from tube count to screen size for the first numbers.
Most Zenith FBT's start with an S-##### & are
marked EIA 343 so Zenith made. They are not a quick
swap so be sure first.
I bet someone has the factory manuals & can check for you.

73 Zeno:smoke:

I only worked on one of those, through the years. The flyback was bad and the Zenith distributor never stocked it, it have to be ordered from the factory.
It struck me as strange, as Zenith always had the best stocks of parts, as well as RCA.
IIRC, that was the model that wasn't very popular and one sold by the early big box stores. A real loss-leader model. :sigh:

...

The Zenith manual for the 20BC50 (CM117S2) says the flyback is a S-87813. But it doesn't give any kind of cross reference.

Now you need a Zenith parts price book to see if any subs. I dont
have one.

73 Zeno:smoke:

Per my 1983 Zenith parts book, it shows that part# S-87813 was first used in 1972 models and superseded by part# 895-735 in 1976. The 895-735 was available for $65.45 back in '83.

Sounds like its a kit. Gotta give them credit still having
the part when those sets were being automaticly junked.
Expensive too. FBT, probably a HOT & a few other tubes
about $175. Time for a new set.....

73 Zeno:smoke:

...

Sounds like its a kit. Gotta give them credit still having
the part when those sets were being automaticly junked.
Expensive too. FBT, probably a HOT & a few other tubes
about $175. Time for a new set.....

73 Zeno:smoke:

IIRC, the set, I replaced the flyback in was about 5 YO. I don't remember it as a kit, just the FB and was no where that pricey.
1983 was a lot later and Zenith had a reputation for parts availability, even on their older products. Too bad, things went the way they did. :sigh:

S-87813 refers to "Horizontal Sweep Transformer & Assoc. Components". It gives separate part numbers for the other components mounted to that board, but not the flyback itself.