TEE Vee Tube fans' SE Cf Amp

[singh santa]

Hello, to all TV tube fans. An SE amp built with all tv tubes.

[Yvesm]

' like it

True pentode CF and bootstraped driver
You should patent that

Yves.

[tubelab.com]

True pentode CF and bootstraped driver

Cool circuit. I built a similar design, but mine was much more complicated, and I didn't have a bootstrapped driver.

I did find and offer another idea. You can easily get a negative supply rail from the top transformer with 2 more diodes and a cap. Then hang a solid state CCS (set at your desired operating current) between the negative rail and the output tubes cathode. Careful bias adjustment can yield zero current through the OPT allowing the use of non gapped OPT's, even mains toroids. The OPT primary impedance is low, like 600 ohms, so mains toroids work well.

I found that the really big sweep tubes like the 6LW6 work best, but a high Gm triode like the 6336A isn't bad either.

You can also omit the bias circuitry and ground the grid resistor. Then a gapped OPT or parafeed cap is needed.

[singh santa]

Many Thanks for all inputs!
here's what it looks.