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Magnavox restoration help.

walloffound

walloffound

AK Subscriber
Subscriber
image.jpeg image.jpeg image.jpeg image.jpeg Hi,
I'm looking for some help to restore a mono tube amp so I can set up my first mono tube system. This is my first tube restoration. I have an ohm meter, amp is discharged, and I know how to solder.
Magnavox 161AA
My to do list:
Add 12ax7 tube
Add fuse
Replace power cord
Replace electrolytic caps
Replace coupling caps.
Rewire octogonal socket to preamp
Replace 5pin socket with fuse holder.
First thing I need help with is a parts list for caps, I plan to order from Mouser
Thank you all!!!
 

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It's pretty simple. To replace the caps, you should replace them with uf ratings as close as possible to the original your replacing. You should meet or exceed the voltage rating and it's ok to go 20% up on the uf rating. MF and UF are the same. So I recently replaced 20uf 350 volt rated caps with 22uf 450v rated. I wouldn't use for arguments sake 18uf or anything rated less than 350 volts.

So go through your amp, write down the components it has you want to replace and then go shopping.
 
So what's the value of the electrolytics
The one has a 23 not sure about the big can, is it 80? Also someone told me that raising the value helps base response
 
I also need help with figuring what value fuse I need and where in the circuit it should go. And what to do with the lightbulb coming out?
 
I see two .047 mfd caps, and one .001 mfd cap. Not sure what the silver one underneath is, but it will say clearly on its shell. The big can will be marked or stamped on the side and should say some thing like "40,30,10 on it no? Just give it a good look. All the voltages will be marked as well
 
That's a multi-capacitor can. 40uf, 30uf, etc. You may be able to find a replacement like these:

https://www.amazon.com/gp/aw/s//ref=mw_dp_a_s?ie=UTF8&k=CE+Manufacturing

You have to match the uf and voltage rating, which may be impossible. Your other option is to cut open the existing can and put new capacitors inside (called stuffing the can), or figure out how to wire them underneath the chasis. Same applies as I said above to values and voltage rating.
 
walloffound said:
The can sais:
40
30
10
20 volt 450
So what is a good replacement for this?
Click to expand...
I have used a CE can with the values if 40,40,20,20 at 525 vdc for that exact capacitor. It has worked in a couple Magnavox amps just fine. The opinion is the little extra capacitance is a bonus. I buy mine at AES. Antique Electronic Supply. Other people use individual caps to build a multi-section or mount them under chassis to save a couple $$
 
Thanks for the info. I get the whole concept of multicapacitor now after reading up about it. I will try to make one since this will be called my Magnavox Shoestring. What about hot rodding. I've read about it here and there not sure what that means. Does it apply to this amp?
 
walloffound said:
Thanks for the info. I get the whole concept of multicapacitor now after reading up about it. I will try to make one since this will be called my Magnavox Shoestring. What about hot rodding. I've read about it here and there not sure what that means. Does it apply to this amp?
Click to expand...
If this is your first rebuild, i personally would buy the CE cap. It is an exact fit. Easy, and what are you saving? $10?? I am about to start my third amp and this one i will use individual caps.
 
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