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Vintage tube amp resurrection with Variac?

I have acquired some vintage tube equipment that has not been turned on for several decades. I bought a Variac on eBay having read many times to be sure to "bring up" old tube gear "slowly on a Variac". What exactly constitutes "bring up slowly"? Is it some sort of staging perhaps? If so, what voltage at each stage, number of stages, how long per stage. Or does it mean to continuously, but very slowly, crank the Variac from 0 to 117 volts?
elunkenheimer
dekay's avatar
dekay
2,959 posts
 
Czarivey:

Your advice does nor gell with the tech that worked on my Pilot 232, nor the advice I received from the AA forums.

Basically I was told that a GZ34 will not start to pass current until it reaches 80-90 VAC (which is 4-5 times higher than one wants to start when reforming lytics).
czarivey
4,494 posts
 
Dekay I mentioned earlier replacing all DC supply caps before even getting onto the variac.
dekay's avatar
dekay
2,959 posts
 
Czarivey:

Also forgot to mention that if using a 5Y3 (in place of a GZ34) it needs to be replaced with the proper tube once you get up to higher voltages (very important point left out).

Sorry, didn't notice the DC cap info.

I once used the light bulb method (think it was on a Pilot 240) and it worked well.
czarivey
4,494 posts
 
In my environment I have to pay rent and make sure that investment in rent is returned. Mostly I restore items I purchased from estates or items purchased in bulk by pound.
Replacing DC caps takes me less than hour on most tube units.
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