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In article ,
says...
I've got a Magnavox RH8524AK08 projection TV that went dead. I bought a set
of boards from an RH8520 from a guy on eBay. The power supply board
indicated in my service manual is the same for both sets (APW007). The
flyback is totally different on the set that I bought; my original has a
tube that comes out at an angle that the HV line slips into and a nut
tightens down. Since the set I bought came with the HV line and splitter, I
replaced the associated parts as well. The TV now comes on.

It's unusual to find one of those relics that still works. We used to
call them "gourmet flybacks from Orville Reddenbacher", you know - not
a one left unpopped ;-) A slight exaggeration, no doubt, but a *lot*
of them blew up. I guess if you have one that survived this long, no
reason not to keep using it.

Another common problem about that vintage was green circuit boards
that used square pins shoved through the board for feed-throughs
instead of plated-through holes. This attempt at cost cutting was a
notorious source of intermittant connections. Some were so bad that
they required repair right out of the box before they could even be
sold.

Is this going to cause a problem?

Aside from the questionable reliability of certain parts already
mentioned, I don't see a problem. There were minor variations for
special versions like the JBL sound system, but basically they were
intended to be compatible. As you have discovered, the HV lead is
different, so just use the one that came with it.

Given the age of the set, is it likely the power supply was changed
at some point?

Fair chance. We used to carry a set of spare boards in the service
truck for elusive problems. Sometimes easier to swap in the home and
rebuild back at the shop where presumably you have better lighting,
more tools, parts, and equipment.

Also, where can I get replacement crt seal kits so I can change the
coolant?

The O-rings between the lens and the cooling chamber are quite durable
and usually reusable. I have not often needed the gasket between the
CRT and cooling chamber except on the rare occasion of replacing a
tube. Philips didn't list these parts separately in the manuals, but
shows one each as parts of the 171677-3 kit. I used to have the
individual numbers written down somewhere but can't find them anymore.