• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Schmitt phase inverter on small heptal pentodes such as 6Ж1П-ЕВ (6J1P-EV, 6Ż1P-EW). Is it possible and does it make sense?

When it comes to tube amplifiers, I am an amateur. I have ECL81 at low voltage and EBL21SE (which requires a few corrections due to the hum caused by the glowing lamps). My next project will be a VT52 (EL32) push-pull with toroids at the output (as in the attached photos). As I have some new Russian lamps and the ceramic stands that go with them, I'm wondering if I could use them for the Schmitt and if they would be able to rock the VT52 Mullard


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An interesting thought that attracted me because I like the ex Soviet submini valves (6N16B and their ilk) and I have some 6J1, 5 and another I forget.

Plus, I have always meant to get time and built a Schmitt inverter, and have failed to make time.

If, my experience of 6N16B, 17B, 21B, 6S6B, 3B, 7B is worth anything, I would say "Yes"

(They are all pretty excellent little valves)

But I am very jealous over the ceramic bases!

Do you have a source you could share?
(I have made my own bases but these look far better!)
Jestem jeszcze na etapie poszukiwań. Przeglądam internet, próbuję coś samodzielnie policzyć... Na razie skłaniam się ku adaptacji części układu Yaqin MC30, który opiera się na tych lampach. Oczywiście to nie Schmitt, ale to sprawdzony system i działa.


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I'm also thinking about changing the concept. Due to the fact that I have 4 SE 7k transformers from UHER reel-to-reel tape recorders, I would make 2 x VT52 SE if I could find inexpensive tubes that, with an 8k push pull transformer, would give me more output power than, for example, a pair of EL84s