My first tube amp.. Magnavox 8802

Morrism

Active Member
I found a console local on CL for $60. It was beat up pretty bad so I did not save the cabinet. Reading the many threads here, I was able to restore it. It's working great.
I copied MIL_Q's idea and used the grill cloth for the front panel.
 

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great looking resto job.
did one myself some time back but not quite as pretty as yours.
good work.
 
I'm thinking of adding volume control. I made a drawing how I think it should be installed.
Does this look right?
Is there any cons to doing this? No audio degradation?
 

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Nice job on your first post. Welcome to AK! Obviously this isn't your first rodeo. As for the volume pot, I'm not an expert on variable resistors, but I'm thinking you can make do without the 47K resistor....
 
Great job! Unfortunately I'll have to hire out to have mine restored. Let us know how yours sounds and what speakers its paired with.

cubdog
 
Nice job on your first post. Welcome to AK! Obviously this isn't your first rodeo. As for the volume pot, I'm not an expert on variable resistors, but I'm thinking you can make do without the 47K resistor....

Thanks for the welcome. I know a little electronics(no degree), but when I started this project, I knew nothing about tubes. Now I know a very little about tubes.
 
Great job! Unfortunately I'll have to hire out to have mine restored. Let us know how yours sounds and what speakers its paired with.

cubdog

I have it playing right now. The speakers are Infinity RS2001 rated 89db and 6ohms. It gets loud, but not so much it's going to hurt my ears. It sounds great! I was surprised.:bigok:
 
that vol control will work ok. try it with and without the 47K and see which is better.
cliplead it in to try. or put it in and then short it with a cliplead.
but I would keep it.
 
All good. If you can get that rusty old chassis painted, powder coated, or anodized you'll feel a lot better. Metal refinishing the transformers to a different brighter color will make you feel the tops! :smoke:

Adding a decent volume pot is all good! Your speakers are efficient enough too.


I found a console local on CL for $60. It was beat up pretty bad so I did not save the cabinet. Reading the many threads here, I was able to restore it. It's working great.
I copied MIL_Q's idea and used the grill cloth for the front panel.
 
All good. If you can get that rusty old chassis painted, powder coated, or anodized you'll feel a lot better. Metal refinishing the transformers to a different brighter color will make you feel the tops! :smoke:

Adding a decent volume pot is all good! Your speakers are efficient enough too.

Did you only look at the first picture? Looks pretty good to me. :scratch2:

cubdog
 
What Fern said,,, I'd add a 1M resistor from the wipers to ground, just in case it lifts or looses contact, the amp will have a path to ground...
 
Yep oops. Ya looks great. Really really good!


QUOTE=cubdog;9041076]Did you only look at the first picture? Looks pretty good to me. :scratch2:

cubdog[/QUOTE]
 
You will want to leave the 47K resistor between the wiper of your proposed volume control and the grid of the input tube in place. This resistor is part of the scheme used to achieve HF stability, which is necessary since this is a NFB amplifier. Removing this resistor will upset that aspect of the design, and so should be left in place.

Dave
 
You will want to leave the 47K resistor between the wiper of your proposed volume control and the grid of the input tube in place. This resistor is part of the scheme used to achieve HF stability, which is necessary since this is a NFB amplifier. Removing this resistor will upset that aspect of the design, and so should be left in place.

Dave

The expert has spoken!
 
The reason I asked about disadvantages to the volume pot mod, Is gordonw posted this circuit that uses a tube for an easy preamp mod. It was for a different Maggie amp, so maybe there is no need for it on my 8802?
 

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What's up with magnavox friends on yahoo? I submitted to join over 2 weeks ago. Then I sent an email and got no reply. Is that group still in operation?
Fortunatly, I found the info I needed to do the restoration here on AK.
 
What's up with magnavox friends on yahoo? I submitted to join over 2 weeks ago. Then I sent an email and got no reply. Is that group still in operation?
Fortunatly, I found the info I needed to do the restoration here on AK.

First off - nice job on that amp! And welcome to AK!

I joined Magnavox Friends several years ago, but there's not much traffic on that site. The admin will check it eventually and get you in.

If you are just looking for a good passive preamp, check out the Schiit SYS - a good alternative to installing a volume pot, plus it has a source selector.

When I refurbished my 8802, I kept it simple, but I did move the input and output jacks to the back to clean up the look.

How about a shot underneath? Did you replace the electrolytic caps?
 
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