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Old 21st March 2013, 08:59 AM   #2701
stajo is offline stajo  Sweden
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Ok good. Show some kind of drawing or description and I can help you find your test voltage.
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Old 21st March 2013, 09:13 AM   #2702
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Stajo do you want that I do like the attached psud?
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File Type: png 26 psu.png (163.9 KB, 147 views)
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Old 21st March 2013, 09:17 AM   #2703
stajo is offline stajo  Sweden
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Start with that and measure voltage over 20k and 30k.
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Old 21st March 2013, 09:25 AM   #2704
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OK
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Old 21st March 2013, 09:28 AM   #2705
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Voltage across 20K 109V, across 30K 165V

N.B. measurements done only with one rail 20K & 30K connected.

Last edited by merlin el mago; 21st March 2013 at 09:34 AM.
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Old 21st March 2013, 10:30 AM   #2706
stajo is offline stajo  Sweden
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ok, im in a meeting, brb in 30
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Old 21st March 2013, 10:32 AM   #2707
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ok don't worry I will wait for you.
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Old 21st March 2013, 10:35 AM   #2708
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Can't be used CCS+Gyrator with OPTs? If can't be used I have to buy a new box and use SSHV2.

Last edited by merlin el mago; 21st March 2013 at 10:39 AM.
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Old 21st March 2013, 11:12 AM   #2709
stajo is offline stajo  Sweden
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Lets do the math first.

So what do we know now? You have 165 volts over a 30 k resistor that ties B+ and ground together. Thats the simulated audio circuit.

Ohms law says U=R*I or the other way I=U/R

165 Volts divided by 30 000 ohms is 5,5 mA

We can check this over the 20 k filter resistor also since all current passes that one also.

109 volts divided by 20 000 ohms is 5,45 mA.

If you should now plug in a tube, biased at 5,5 mA (bias is controlled by the resistor between cathode and ground in the relation to B+) you should now have 165 Volts B+.

Are you with me on that? Shall we try?
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Old 21st March 2013, 11:16 AM   #2710
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OK I will try with one tube.
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