Help Identifying a PT

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yalesmith
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Location: Orange County NY

Help Identifying a PT

Post by yalesmith »

I purchased a red bear amp and it came with 2 power trannies, a 220 and a 120 volt. I am trying to identify the 120 volt PT. The markings are as follows

TF-77-P-S
606541

The amp sounded so horrible I gutted it.

Thanks
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ToneMerc
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Re: Help Identifying a PT

Post by ToneMerc »

yalesmith wrote:I purchased a red bear amp and it came with 2 power trannies, a 220 and a 120 volt. I am trying to identify the 120 volt PT. The markings are as follows

TF-77-P-S
606541

The amp sounded so horrible I gutted it.

Thanks
The TF part number is an assigned discrete part code. The PT manf code of 606541 is Schumacher(606),possibly made the 41st week of 2005 is my guess.

TM
yalesmith
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Location: Orange County NY

Re: Help Identifying a PT

Post by yalesmith »

Okay, that helps alot but i think it is alot older than 2005 though.....It has cloth leads, etc....So was Schumacher any good? (i thinked they made alot of fender transformers) and are they still aroud? I looked and found a website but does not look like the same company.

any and all help is appreaciated.

thanks
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ToneMerc
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Re: Help Identifying a PT

Post by ToneMerc »

yalesmith wrote:Okay, that helps alot but i think it is alot older than 2005 though.....It has cloth leads, etc....So was Schumacher any good? (i thinked they made alot of fender transformers) and are they still aroud? I looked and found a website but does not look like the same company.

any and all help is appreaciated.

thanks
Pick your decade then...... 65, 75, 85, 95

http://www.batterychargers.com/Content. ... ansformers

TM
Firestorm
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Re: Help Identifying a PT

Post by Firestorm »

Unless the transformers are aftermarket, I would be hugely surprised to see Schumachers in a Red Bear. Everything else in those amps was Russian AFAIK. Unless when Gibson was importing them, they added the iron here...
yalesmith
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Re: Help Identifying a PT

Post by yalesmith »

I really would like to get an idea what the ratings are, I know there is way of measuring it safely....Is there an easy way of doing it?
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Phil_S
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Re: Help Identifying a PT

Post by Phil_S »

Well, you know what tubes is was pushing, so get the spec sheets and add it up. Beyond that, testing gets dicey at best.

When I'm working with an unknown, I build a solid state rectifier, add some caps and hang a resistive load on it. (Include a switch, fuse, etc.) Start with a large load and work your way down. As you reduce the load, it will pull more current (simple application of Ohm's law). The load has to be adequately rated for wattage and it gets extremely hot. You don't want to go too low, or you will let the smoke out. As you know, once you let the smoke out, you have an answer, but you can't put the smoke back in it. I keep a fire extinguisher nearby, and I use a power strip with surge breaker, too. At the first sign of smoke, shut it down. Rely on your nose -- you'll smell it before you see it, and you don't need to ask me how I know this. If you have a cold, wait until you don't.

When you detect warmth on the PT, but no smoke, you are getting there. It's a guess at that point. It is unwise to push the envelope.

If you feel like reading, Google is your frenemy. Search for, "rating of unknown power transformer" and you'll get more that you want to read.

I like this one: http://www.diytube.com/phpBB2/viewtopic ... 65&start=7
passfan
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Re: Help Identifying a PT

Post by passfan »

Here is a link to an article that tells you exactly how to find the current ratings of a power transformer. the filaments you can calculate by using the data sheets for the tubes that were plugged in...adding up the filament currents.

https://tubeamparchive.com/viewtopic.php?t=13747

Oops...Phils link was quicker :D
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ToneMerc
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Re: Help Identifying a PT

Post by ToneMerc »

yalesmith wrote:I really would like to get an idea what the ratings are, I know there is way of measuring it safely....Is there an easy way of doing it?
As a first option you could contact Schumacher and ask for the specs of that TF code. They may possibly give them to you.

TM
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Phil_S
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Re: Help Identifying a PT

Post by Phil_S »

IS W/S still in business? My web search turned up nothing. Of course, as we all know, if Google doesn't find it, it doesn't exist :shock:

One time, I got a reply for Foster on such a question, and it was a very old PT. Those guys are engineers. I don't think they toss anything. Ever.
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ToneMerc
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Re: Help Identifying a PT

Post by ToneMerc »

Phil_S wrote:IS W/S still in business?
Yes, I posted the link above.

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passfan
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Re: Help Identifying a PT

Post by passfan »

I tried them once on an organ transformer and was told they don't have any files left from those older transformers. I got the impression they're into the newer technology now.
"It Happens"
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yalesmith
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Re: Help Identifying a PT

Post by yalesmith »

Yup. I called up Schumacher and i got the I dont care, I wont even bother acting like i care vibe. Not sure if i should i be annoyed or it is understandable...but you would hope the company would provide some data, support not at all.
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