• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

ecc802s SRPP preamplifier

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hello,
i have finished a preamplifier with the ECC802S Tesla tubes. The circuit diagram is here: DIY ECC802S (12AU7 / ECC82) Vacuum Tube SRPP Preamplifier
The schematics shows on the tubes pins 6 about 215volts. I have only 205volts and i am using the same power supply but with larger capacitors.(not 3x100uf but 3x470uF). Maybe my tubes draws a little more current. Is this voltage ok? Also i have a problem with the heater voltage. I am using the LM317 to supply 6,3vdc. Without the tubes i have 6,3v but when i put the tubes on the heater voltage drops to 5,8v possibly because the transformer cannot supply the current needed.(the transformer voltage drops from 8 to 7Vac with the load) Is this ok or i must rewind the transformer? (i made the transformer by myself).
Thank you
george
 
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