****** 1.5" OT and 2.5" PT just in!

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joshwilson3
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****** 1.5" OT and 2.5" PT just in!

Post by joshwilson3 » Sun Jan 21, 2007 2:14 am

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Last edited by joshwilson3 on Sat Feb 01, 2014 12:26 am, edited 1 time in total.

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VelvetGeorge
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Post by VelvetGeorge » Sun Jan 21, 2007 5:58 pm

Looks great! You can expect approx 485V B+ using the higher taps and 445V B+ using the 170V taps. This will vary a little due to input AC, filtering bias ect.

VG
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yngwie308
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Post by yngwie308 » Sun Jan 21, 2007 9:29 pm

Is the Old Black Flag PT the same dimension?
http://i57.photobucket.com/albums/g219/ ... 000133.jpg
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joshwilson3
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Post by joshwilson3 » Sun Jan 21, 2007 11:07 pm

yngwie308 wrote:Is the Old Black Flag PT the same dimension?
http://i57.photobucket.com/albums/g219/ ... 000133.jpg
yngwie308
It looks like it. That would make it a 2.5". I think I've read there was a 3" power tranny used by Marshall back in the day as well. I don't know what amp it would have been in though.

What year is the amp in that pic?

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Flames1950
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Post by Flames1950 » Sun Jan 21, 2007 11:11 pm

Black Flags had a 2.5" stack as well. The 3" was for the early 100 watters that had terrifying B+ voltages of up to 560VDC.
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Post by joshwilson3 » Sun Jan 21, 2007 11:21 pm

VelvetGeorge wrote:Looks great! You can expect approx 485V B+ using the higher taps and 445V B+ using the 170V taps. This will vary a little due to input AC, filtering bias ect.

VG
Thanks George. What power trannys do you use for your master volume builds? And what B+ do you normally get?

Will this power tranny work with a master volume circuit? I'm not familiar with all the tabs on the back, so I was wondering.

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Post by Brian Wallace » Mon Jan 22, 2007 8:35 pm

Is the Old Black Flag PT the same dimension?
http://i57.photobucket.com/albums/g219/ ... 000133.jpg
yngwie308
The 1203-80 had a 2.5 inch stack and a standard 3 x 3.750 bolt pattern. The 1204-43 was the 3 inch stack PT and yes, it had a 560VDC plate voltage. :wink:
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Post by VelvetGeorge » Mon Jan 22, 2007 8:45 pm

I use the stand up mount with the same specs. Usually about 485V B+.

VG
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Post by mightymike » Tue Jan 23, 2007 4:58 am

I have the same tranny but my high taps are 472, and my low taps are around 435. I use George's dual tap switch, and between that and the variac. I can go from 472 down to 435, without even comming close to being too low on my heaters, then if I want to go lower, I switch to the lower taps, and go from there all the way down to 390 and still have 2.9v on each heater to ground.

I love that flexibility.

You could do the same with George's, butI wish his lower tap was a 450, for the most flexibility, for the way I would use it for all points between 500 down to 390.

Lots of great tones in that range.

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