• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Magnavox 8608-10

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Found this on another site....props if it's yours. Can someone confirm this for me? Not sure on the 3A fuse, but yes on the SB.
Power.jpg
 
The Audiophile Talk site was hacked. No backup exists. Years of posts have been lost. :bawling:

Damn and blast the @sshole(s) responsible. As no money was to be made by the damage, I can't help but think of a sadist who pulls wings off flies. :mad:

A while ago it happens that I saved a copy of this top rated thread:
Bargain Basement.
Hope it can be useful
Unfortunately, when I try to upload this pdf file, I receive this message:

"Your submission could not be processed because a security token was missing.

If this occurred unexpectedly, please inform the administrator and describe the action you performed before you received this error."

The full Audiophiletalk print page, containing the "Bargain Basement" thread , is a 10680 kb pdf file.
 
Thanks Mosquito.... I bought power switch, fuse & holder, & LED...but I hope this isn't a stupid question. Since I'm bypassing power from the tuner ( & nothing in the umbilical has continuity within itself), can I just remove the umbilical & all wires to it? I'm guessing this is part of why the 390 ohm resistors are needed....Thanks
 
She breathes Boys......& sounds sweet! Just temporarily checked my 3-wire power cord, Power switch, SB fuse, and 390 Ohm mod. It was hooked up to bookshelf Bose ( not my Chorus II's ) just to see. Initially, channel 2 popped & cracked just a bit....then after about 7-8 minutes, channel 1 started distorting a bit. It could be the speaker wire was just twisted around the existing connectors. I'm going to replace all tubes, rectifier, caps (including can) and put in dual binding posts for speakers.
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I would definately get 4 separate caps under the chassis for that, rather than using the 4 in the can. My 8802 sounded miles better after i did this.

+1 on not trusting that 50 year old can electrolytic. You are rolling the :dice:

I'd also recommend checking the coupling caps just up stream from the power tubes for leakage and cleaning and retensioning tube sockets. Bad coupling caps can cause the 6V6s to run too hot. A small value resistor (1, 3 and ten ohm are all common choices) added on the cathode will allow you to check tube power.

I'd also recommend looking at a two section cap such as the JJ 500-50-50 at antique electronics. They can mount in place of the existing can with a clamp and they look good too. There are other brands too like the one in Had's headphone amp. It's kind of a struggle to get four caps mounted securely under the chassis and the JJs cost little more than you'd spend on a pair of caps. Antique electronics also sells the orange drop caps (EDIT: 716P) that most of us would use to replace the coupling caps.

You are off to a good start.
 
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The caps i used for coupling were Jupiter vintage tone caps (mostly used for guitar amps so ive read to believe)... They give a lovely smooth inviting sound when using this amp, especially with mellow mood music (seems to lose it somewhat with more lively music).

Also these values were changed from 0.047 + 0.0047, to 0.1 + 0.01 (which gave a much needed bass boost).
 
I've got all new caps including a new can. Also, resistors that are out are being replaced as we speak. Can someone explain the can replacement for me. The new can is stuffed already, but the posts have funny symbols on them. I've read to put one on C1A, 2 on C1B.....etc. do I just tie two + ends together? Thanks
 
Thanks so much for the info, I appreciate your knowledge. I have a degree in electronics - but I don't use it daily (I fly helicopters), so....not sure I'm capable of all that fabrication. Replacing caps, tubes, checking resistors - I can handle that. Is there a tutorial handy explaining rewiring for the 12AX7?


Flying helos is more fun. My brother is building a kit helicopter, against my advice. I believe in the Bell 47 Theory of rotary wing aviation but that is another story. I want to get the rating but I could never justify it economically.


If I had a console in that good a shape I'd leave it intact, i would recap it and claen it out and that's it.

You will want a tube manual so as to have the pinouts of all the tubes you will run into commonly. These can still be bought as reprints from suppliers like tubesandmore dot com or downloaded from Pete Millett's web site.
 
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