Tranformer help needed

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azatplayer
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Location: Great Southland

Re: Tranformer help needed

Post by azatplayer »

Ive seen 2 schems for this amp. One had a 25k the other 50k bias pot.

One had a 40/20/20/20 can the other ran a 50/50 plus a 47. Seen inside 2 amps, one had the 50/50 and 47 the other, an earlier one had a 50/50 and a pair of 22's in parallel, same thing. The 40/20/20/20 is someones take on it. Has some parasitic issues.

Great amp with a zendrive!
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M Fowler
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Location: Walcott ND

Re: Tranformer help needed

Post by M Fowler »

I also have two different gut shots one definately has the 40/20/20/20 can cap.

The other gut shot shows an extended board with two caps on that. There is what looks like a 50/50 cap can used there.

I will take from all that I see and make my clone from that.

Painted the chassis black and put it back together tonight. Not sure what I will do about faceplate right now want to use a local supplier if I can.

Mark
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M Fowler
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Re: Tranformer help needed

Post by M Fowler »

Well I fired up the amp last week and need to get my voltage down to keep from red plating but got some more resistors coming as well as the 1k 25w cement resistor.

Loud as hell and very little hiss which is a plus. When I get back inside the chassis I will take more pictures of the circuits. I really need to sit down and figure out how to use the digital recorder I just got Zoom H4.

So when I do a recording do I upload to a host site then to AG?

Mark
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FunkyE9th
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Re: Tranformer help needed

Post by FunkyE9th »

So did you end up sticking with the JTM transformers?
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Structo
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Re: Tranformer help needed

Post by Structo »

You can upload to www.soundclick.com it's free.

What I do when I need a quick sample is use my Canon digital camera.
It also shoots video. Then I upload it to Photobucket.

The mic is crap but if the amp isn't too loud it doesn't clip too bad.

That is a good looking amp.

I have used waterslide decals before for labeling, then clear coated over the top with Deft clear nitro lacquer.

But it's hard to make light colored letters on a black background because the printers black isn't as black as the paint.

On the 6V6 amp I built I may paint the face gold then use clear decal paper with black lettering.
Then bury them in lacquer.
Tom

Don't let that smoke out!
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M Fowler
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Location: Walcott ND

Re: Tranformer help needed

Post by M Fowler »

Yes I did for now but I am sure I will yank these out after a bit and use them in a JTM45 build and get the correct trannies for this amp with 50v bias tap and UL taps on the OT.

It sounds good but need to lower the voltage before I wreck these tubes. I need to get back inside this amp and take more readings. I want to solve all the issues so I can document this build. I think if someone follows the schematic and use the layout for postioning it would be very close to a Dr Z Rt 66.

Right now I have this RT 66 on the bench, an exact TW Express build and a 80-100 watt Express. I need to finish the Rt 66 first. :roll:

Mark
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M Fowler
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Location: Walcott ND

Re: Tranformer help needed

Post by M Fowler »

Structo,

Thanks for the link I need to get some clips of my amps done.

This is a RT 66 cab but there sure isn't much room left over with those KT66 in there. :)

Mark
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