Huge magnavox Combo roundie Warren MI

[Kalamazoo-DJ]

There is also a board right under the CRT but it cannot get a good view of it for you

[DaveWM]

sorry cant see it, someone fam with this chassis will be able to help out forsure.

[Charlie]

DJ, one of the first things you need to do is clean that chassis up a bit. Looks like there's a decent amount of dust on there, and that by itself can cause problems. For a start, get a small delicate brush... something like a woman's make-up brush. Start dusting off those boards and have a vacuum cleaner hose nearby to suck it up as you brush the dust. Be careful not to bump any standing naked coils... there's a green one there to the left of the power tranny... those break easily. The dust on there can allow voltages and signals to jump across to parts where it's not supposed to go. You can also load down the HV section by having too much dust in there.

I'm not sure what that chassis is... looks backwards. Perhaps it was Magnavox's own design? I would have assumed this set to have a CTC15 or 16 clone in it... doesn't look like one of those.

[Kalamazoo-DJ]

Ok I was just wondering about how to do that cleaning, should I attempt the lightbulb test on this once it is clean? I do not have my meter with me today for testing the system ohms etc.

[Charlie]

If that thermistor is part of your power supply, you're not going to be able to do much without replacing it first since the toasted thermistor won't allow any juice to get to the rest of the set. You might be able to jump it (especially since you'll be applying low power to the set anyway).

Until you get a Sams for the set, you're not going to be able to do a lot. You should wait till you get the Sams.

[Kalamazoo-DJ]

Ok where is a good source to get them?

[Charlie]

http://www.samswebsite.com/photofact/pf_search.asp

[Kalamazoo-DJ]

When I looked up the chassis 4251 I came up with 9 RCA options

[Phil Nelson]

I would second Charlie's advice to hold off until you get the Sams service manual. Poking around in the dark and powering it up a lot is not the best idea at this stage.

In the meantime, you can clean off the dust & grime and brush up on your schematic reading and soldering skills.

It's usually prudent to replace all electrolytic capacitors. This article has basic advice about recapping.

http://antiqueradio.org/recap.htm

Here's what a dead thermistor looked like in my RCA CTC-11A.



A disc roughly the diameter of your thumb, with two metal leads. I replaced it with a new type CL-90. There may be other types I'm not aware of.

Phil

[Kalamazoo-DJ]

Thanks Phil, I will keep looking so far nothing like that, and still having trouble with the chassis number being 9 different RCA's on Sams not sure whats going on with that

[Charlie]

Those RCA numbers are not for you. It just so happens that those 4 digits you entered are part of someone else's model number. I just looked up 4251... online and in my own index... that doesn't bring anything up for Maggies of that time. Try and find another number. Magnavox's are sometimes a pain in the ass with model numbers. I think the number you want will likely start with a letter... like "T" or "U" for the first character... and likely several numbers to follow.

[Kalamazoo-DJ]

I will keep looking around in it

[ChrisW6ATV]

I have been able to re-solder two of those thermistors by scratching the disc surface clean/shiny where the original "blob" was and re-tinning them there.

[Kalamazoo-DJ]

THis is the only model number I could find but sams has no record of it.
10T558K

[bgadow]

If we can narrow down the sams number I'm sure I can fix you up with an original copy. It's getting late tonight; if you don't figure it out in the meantime, maybe I can research it some Monday night. With a few details I bet Randy Bassham could I.D. the chassis.