come inside, please: edumicate me about clone tranny's

[Photios]

I've got a rare amp that I'm gonna clone: a Wizard Vintage Classic...I'm guessing this one hasnt been done before by anyone here(?).

I'd like to know how I can get some tranny's for my clone that are exactly like the originals (or at least very, very similar) without destroying these original tranny's. Are there ways to use a scope or a variac or something to get the specs from a tranny?

[Phil_S]

Unwinding them is the only sure way to clone them. When you unwind, you find the number of turns, what kind of wire, core, etc. Short of that, you make a best guess.

IMO, the PT is much less critical. Figure up what the tubes draw for filament and B+ current, and get a bit extra. Disconnect it, get the unloaded secondary voltages and take careful note of the primary input, which is changes at the whim of the power co. and what your neighbors are doing. Take ohm readings on the windings.

The OT is trickier and probably more critical to tone. Unhook the primary and the secondary. Ohm the windings. Then feed low voltage to the primary and check what comes out the secondary. This tells you the turns ratio. Since you know the tubes, you can guess at the impedance ratings and get them right.

If you have an LC meter, check the inductance of each winding (in Henries) and that tells you something, as well.

Estimate the core sizes.

Consult with a specialty house like Heyboer or Mercury Magnetics and see if they can take an educated guess with the info you provide.

Another thought...if there are EIA codes on the trannies, you might find the manufacturer is still in business. There is always a remote possibility of finding a spec sheet or schematic. I should tell you, this is poossible as I know it from personal experience. I had an old Heathkit PT, contacted the manufacturer, somehow got to one of the senior engineers, who pulled the schematic from the vault. Strange things happen.

[Photios]

OK, so if I'm willing to sacrifice the current tranny's, one of the transformer companies (DeYoung, Mercury, Heyboer, Pacific, etc) will reverse-engineer these? I guess then I could order 2 new sets based on their findings: one set to replace the sacrificed from the original amp and one set for the clone, yes?

[philmanatee]

I don't know if they still do, but I think mercury used to offer replacement transformers for wizard. Phil

[skyboltone]

OK, so if I'm willing to sacrifice the current tranny's, one of the transformer companies (DeYoung, Mercury, Heyboer, Pacific, etc) will reverse-engineer these? I guess then I could order 2 new sets based on their findings: one set to replace the sacrificed from the original amp and one set for the clone, yes?

Mercury doesn't sacrafice anything. They take measurements and return the transformers unharmed to you. They also don't share much of what they find with you but you will find out primary and secondary impedences on the OT.(Which I knew already) They will clone you as set based on what they find. I recently gave them a set of AO-35 Hammond Trannies to look at. They said they'll build them for me at the "Good Guy" rate. Whatever that means. Paul is a great guy to deal with but as has been said many times here and elseware, they are pretty proud of their stuff.

Dan H

[Photios]

Thanks for the replies all...looks like I'll be calling MM on Monday...I'll post the results.

BTW, has anybody cloned a Wizard before?

[rhinson]

the wizard trannies ARE mercury magnetics---sergio and rick (the wizard builder) designed these. they used to offer them in their listings while rick was on the road and not building, but i believe he's back in production now and i think he requested merc take them out of their catalog for the general public to buy. since you are an owner, you might contact rick and see if you talk him into letting you get one and keep as a "spare" in case yours smokes. these are just offshoots of their marshall plexi models. rh