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Hoffman Amps Forum image Author Topic: PT Transformer choice  (Read 2383 times)

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Offline Oddvar

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PT Transformer choice
« on: July 04, 2019, 12:56:36 pm »
I am about to build a Trainwreck Express from parts that I mostly have in my drawer.  I have a Weber 40w and was wondering if I could use that.  What will I loose, is it possible? or any other idea for not using it?  I have enclosed a pic of it and a Classic Tone meant for TR Express.

I don't understand PT's much, so a good explanation would be nice

Offline sluckey

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Re: PT Transformer choice
« Reply #1 on: July 04, 2019, 01:05:45 pm »
Here's a pretty good discussion by some trainwreck folks...

     https://ampgarage.com/forum/viewtopic.php?f=1&t=32132
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline jbrew73

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Re: PT Transformer choice
« Reply #2 on: July 04, 2019, 09:42:51 pm »
Isn’t the OP the same in the amp garage thread?

Offline Tony Bones

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Re: PT Transformer choice
« Reply #3 on: July 04, 2019, 10:01:10 pm »
Isn’t the OP the same in the amp garage thread?

Yes, no, doesn't matter. That thread answers all of the OP's questions.

Offline sluckey

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Re: PT Transformer choice
« Reply #4 on: July 05, 2019, 12:17:05 am »
Isn’t the OP the same in the amp garage thread?
No, that's Oddvar R over at TAG.   :wink:
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline MFowler

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Re: PT Transformer choice
« Reply #5 on: July 05, 2019, 12:03:50 pm »

To get the correct plate voltage use the 300v HT taps.


The Express can be built with either 5k2 or 6k6 primary OT.


The PT & OT do not have to be rated for 300mA or 50W rating you can use lower mA or wattage ratings.


Try 6V6 tubes and you may have your perfect amp.


Mark

 


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