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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Help with these Russian GU50 tube amplifier

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>>>> There is 30V at the PS, I have no idea where it goes.

+30V applayed to filaments for AC "Hum-m-m!" noise cancellation. Just solder together points "A" on PSU schematic.

Hello
Would you be so kind please help me with these +30 on the PSU circuit.
I do not have center tap (or A point) at 6.3V and 12V heater..
Where I connect the +30 in my case or just leave it out?
Please take a look at my parts I have for these amp PSU!
I also purchased a par OPT 3.5K 10W 100mA continuous bias.. Al together I have 90-95% of the parts.
I would love to test the amp but with that +30 I don't know what to do..
The 12V for the GU50 is a separate transformer also I have DC PSU for the GU50 if that is better all do that is only 2A the AC is 5A.
Thanks
Greetings Gabor
 

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Hello
Would you be so kind please help me with these +30 on the PSU circuit.
I do not have center tap (or A point) at 6.3V and 12V heater..
Where I connect the +30 in my case or just leave it out?
Please take a look at my parts I have for these amp PSU!
I also purchased a par OPT 3.5K 10W 100mA continuous bias.. Al together I have 90-95% of the parts.
I would love to test the amp but with that +30 I don't know what to do..
The 12V for the GU50 is a separate transformer also I have DC PSU for the GU50 if that is better all do that is only 2A the AC is 5A.
Thanks
Greetings Gabor

You do not need this.

Look: http://www.diyaudio.com/forums/tubes-valves/211731-heater-wiring-good-bad-ugly-7.html

post 69. It is really works.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.