'62 Magnavox console sound problem

capacitors

ok, I've located the coupling caps, and, just visually, they obviously need replacing. leaking fluid.

Should I be replacing all the disc caps as well? they aren't labeled, so I've no idea what to buy. Where does one get a schematic for these old things?

And while we are at it, should I be pulling the tune/preamp assembly and replacing caps in there as well? (I think I already know the answer, but pulling that assembly is a LOT more complicated)
 
Disc caps usually last forever. Most of what needs replacing will be the coupling caps and the can cap. fair wager the rest is OK. If it needs some resistors, you can test them in circuit and replace any that read high out of tolerance. I would check the values on the resistors soldered to the can cap though. They are often off value, and even if they are not it can be easier to just get new ones rather than recycle the old ones.

Same type of deal in the preamp, but I'd get the amp going first. Many of the parts in the tuner will be fine, but there are likely a handful of those wax paper caps that could stand changing, and there may be a filter can as well.
 
I'm trying to find the new coupling caps I need and it's surprisingly hard to find the right match. The caps say .047 MFD and 450 volts. See photo. I think it is electrolytic.

The closest I can find are these caps from tubes and more. But they are listed as "Polypropylene Film" which doesn't seem right.
https://www.tubesandmore.com/products/C-MCC-600
 

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That is a poly or PIO cap. The only electrolytics in this amp is the multi section can cap mounted on top of the chassis. The coupling caps are all common easy to find values. You can use Sprague Orange Drops availablr from Antique Electronic Supply or the Dayton Audio from Parts Express. I used the Dayton's in mine and ate totally pleased with them. Good luck.

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I'm trying to find the new coupling caps I need and it's surprisingly hard to find the right match. The caps say .047 MFD and 450 volts. See photo. I think it is electrolytic.

The closest I can find are these caps from tubes and more. But they are listed as "Polypropylene Film" which doesn't seem right.
https://www.tubesandmore.com/products/C-MCC-600

On the coupling caps, the sprague orange drops you're looking for are 600 Volts. I used the 716p. I got mine at Just Radios out of Canada. He also has a pretty good write up on cap replacement. Helped me a lot when I recapped one of these this Spring.

You've heard it already, but I strongly recommend the left hand in your back pocket method. It also won't hurt to come up with some sort of bracket to hold the amp while you're working underneath. I shorted the first filter cap across my chest and let's just say I NEVER EVER WANT TO DO THAT AGAIN!!!

I'd also look into making a simple Dim Bulb Tester. Dumb mistake cost me one of my Smokey Mullard 6BQ5s.
 
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Discharging the can is very simple. Take a test lead...insulated alligator clips on both ends...Attach one end to the chassis first
The other gets attached to the plate of one of the output tubes. For your amp that would be pin 7. Be sure to attach to the chassis FIRST. Let the there for a minute or so before you start work. I leave the lead attached the wholen tjme I'm working on the amp. And definitely change out the coupling caps...there's like 4 of them...about $10 investment. If they're not leaking they will soon enough.





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Wait, what?? First off, are you discharging the caps through the output transformer? Second, how can you " leave the lead attached the wholen tjme I'm working on the amp"? Isn't that shorting the plates to ground?
 
Wait, what?? First off, are you discharging the caps through the output transformer? Second, how can you " leave the lead attached the wholen tjme I'm working on the amp"? Isn't that shorting the plates to ground?

When I was a little kid, my dad was an electronics tinkerer. I remember him reaching into the back of a TV set or something else full of tubes with a big screw driver. "Stand back," he'd say. "I have to discharge this capacitor so it doesn't knock me on my fanny later." He seemed to speak from experience.
 
Steve; Sounds like dad was discharging the caps for Hv section. 15Kv to 25Kv will knock you across the room and dent the drywall. I was helping Dad one time with B&W (I was about 10 at the time)Tube TV(it was our 60 or 61 Silvertone B&W with a Brn metal case) holding a meter probe on a cap lead near the flyback. I was told not to move my arm, and , well a bit of inattention got to me and my arm moved slightly, and ZAP, OWWWWWW! THUNK! The opposite wall was about 8 ft away and I landed right up against it. Knocked me silly! It took a VERY LONG TIME before I got behind another Tube TV with the back off, and I would locate the Flyback 1st and stay the hell away from it.

Triode17: As long as you have the unit OFF AND UNPLUGGED it should be OK. He just has to remember to remove the jumper each time he wants to power it up.
 
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