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Old 20th March 2013, 09:23 PM   #2671
stajo is offline stajo  Sweden
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Quote:
Originally Posted by merlin el mago View Post
Filament trafo haven't center tap. I use one separate for each tube filament.
I ment B+ trafo
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Old 20th March 2013, 09:24 PM   #2672
vgeorge is offline vgeorge  Greece
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If the tubes are OK, check your wiring on the cathode, as suggested. There is no current draw.
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Old 20th March 2013, 09:24 PM   #2673
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Quote:
Originally Posted by ErikdeBest View Post
So you have the + and - of the filament regulator across the filament of the #26? In other words, you do not have it across the filament AND the cathode resistors?
+ reg goes direct to filament, - reg goes to 10R and continues to filament

Last edited by merlin el mago; 20th March 2013 at 09:30 PM.
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Old 20th March 2013, 09:26 PM   #2674
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Originally Posted by stajo View Post
I ment B+ trafo
I have two 125VAC to get 250VAC, so between each trafo is the center tap for B+?
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Old 20th March 2013, 09:28 PM   #2675
stajo is offline stajo  Sweden
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Quote:
Originally Posted by merlin el mago View Post
I have two 125VAC to get 250VAC, so between each trafo is the center tap for B+?
Yes

For filament circuit check your own schema #2597

It must go to ground as in that schema, not float
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Old 20th March 2013, 09:30 PM   #2676
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Quote:
Originally Posted by merlin el mago View Post
+ reg goes direct to gilament, - reg goes to 10R and continues to filament
Hi Merlin. I just checket your pictures in post 2593 and it looks as if you do not have a connection from the end of the resistors to ground. As you said: the whole thing is floating.

So, + reg goes to one side of the filament, other side of the filament goes to 10R resistor, other side of the 10R resistor goes to - reg. This - reg should also be connected to ground of the amplifier!
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Old 20th March 2013, 09:31 PM   #2677
vgeorge is offline vgeorge  Greece
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You are saying that you are using two 2x125ac transformers? Kindly clarify you setup exactly.
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Old 20th March 2013, 09:34 PM   #2678
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Quote:
Originally Posted by stajo View Post
Yes

For filament circuit check your own schema #2597

It must go to ground as in that schema, not float
Click the image to open in full size.

I haven't grounded the cathode resistors, Rod told me his filaments regs must be connected floating never connected to ground.
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Old 20th March 2013, 09:36 PM   #2679
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Quote:
Originally Posted by vgeorge View Post
You are saying that you are using two 2x125ac transformers? Kindly clarify you setup exactly.
George I don't see any difference using 2 x 125 VAC or 1 x 250VAC, I don't understand what's the difference?

TIA
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Old 20th March 2013, 09:41 PM   #2680
vgeorge is offline vgeorge  Greece
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Have you taken the center of the two transformers to ground? Are the transformers 125ac or 2x125ac? How have you wired them?
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