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Hi to all coilers. I have been readin about VTTC for a long time and i have diceded to build one. I have about 40 russian lamps rated at 22kv 350ma. So i was wondering what i could achiev with them. Is it possible to post some more specs about your coil Christopher Miles.
Registered Member #29
Joined: Fri Feb 03 2006, 09:00AM
Location: Hasselt, Belgium
Posts: 500
Wow Chris..I am impressed!
Steve, I once built an audio amp that operated a tube in "common grid" mode with a BJT driving the cathode. It worked quite well. In effect, it is very much like cascode topology. High gain with excellent isolation. The transistor only ever sees low voltage. I imagine this would work well as an audio modulator for a vacuum tube RF amplifier...like in an audio modulated tesla coil!
Registered Member #76
Joined: Thu Feb 09 2006, 10:04AM
Location: Hemer, Germany
Posts: 458
mh, there is a shematic on a german website wich uses a mosfet to drive the screen grid of a pentode, wired as an rf oscillator driving a one coil plasmatweeter. Works just fine. This is the same magnat an some other factorys used in his plasmaspeakers
Registered Member #89
Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145
Hey, steve, I have zero experience with these things, but, How is such modulation actually done? Class A? If there was a point where mosfet is fully ''off'' and tube is ''on'', the mosfet would go ''bang''... ?
I also noticed people using triacs on the cathode itself for modulation, while using 4kV power supply? What prevents the triac from getting blown at that point?
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8Kva Quad 833C VTTC
What does the MOSFET do, is it hooked between the tube cathode and ground?
