http://www.diyaudio.com/forums/showthread.php?s=&postid=808836#post808836
Yes, I have been reading this from time to time, and I don't know whether it would work or not. I have done some experiments using a "chokeless parafeed" circuit whic uses a SS or pentode CCS to feed a triode. This works well, but some of the intricate details in the music is missing. I have also tried using a CCS IC to load the other half of a P-P transformer. The results were similar. I think that the DC current flowing through a well designed SE transformer keeps the transformer in the linear part of its magnetic curve. It also minimizes the hysteresis effects.
I will get back to these experiments sooner or later. I would like to experiment with a toroidal OPT since the magnetic circuit is smaller, and these effects should be lower. For my 833A amp, I will use a conventional SE OPT since this will operate at 1500 to 2000 volts. I don't have any pentodes capable of this voltage, and mosfets will emit too much smoke.
And making artificial lightning isn't? I am all for crazy experiments, but I was about 500 feet away when my friend performed the pole transformer experiments. It made a big plasma ball, and a wicked sound, but I expected a big bang, it didn't happen. When he tried connecting the transformer directly to the generator, the breaker blew. I suggested using a 1KW halogen lamp as a ballast, but it limited the current to much. We needed a bigger light bulb.
Yes, I have been reading this from time to time, and I don't know whether it would work or not. I have done some experiments using a "chokeless parafeed" circuit whic uses a SS or pentode CCS to feed a triode. This works well, but some of the intricate details in the music is missing. I have also tried using a CCS IC to load the other half of a P-P transformer. The results were similar. I think that the DC current flowing through a well designed SE transformer keeps the transformer in the linear part of its magnetic curve. It also minimizes the hysteresis effects.
I will get back to these experiments sooner or later. I would like to experiment with a toroidal OPT since the magnetic circuit is smaller, and these effects should be lower. For my 833A amp, I will use a conventional SE OPT since this will operate at 1500 to 2000 volts. I don't have any pentodes capable of this voltage, and mosfets will emit too much smoke.
Ive played with some big Jakob's ladders, but messing with a downed pole pig is nutty
And making artificial lightning isn't? I am all for crazy experiments, but I was about 500 feet away when my friend performed the pole transformer experiments. It made a big plasma ball, and a wicked sound, but I expected a big bang, it didn't happen. When he tried connecting the transformer directly to the generator, the breaker blew. I suggested using a 1KW halogen lamp as a ballast, but it limited the current to much. We needed a bigger light bulb.
Of course it is. Id be concerned about damage and shock in the case of the downed pig is all, though I dont have the specifics of this case. From what I understand, most people killed by hurricanes are killed in the aftermath.
Ive let some smoke out of stuff trying to ballast big transformers, it is a bugaboo for many high voltage experimenters. Putting a welder with shorted secondaries in series is one popular approach, another method is using water heater or oven elements as resistive ballast.
Ive let some smoke out of stuff trying to ballast big transformers, it is a bugaboo for many high voltage experimenters. Putting a welder with shorted secondaries in series is one popular approach, another method is using water heater or oven elements as resistive ballast.
Yes, most hurricane deaths (at least in Florida) happen in the aftermath of the hurricane, often due to carlessness or just plain stupidity. Two people that I knew were killed in the days following hurricane Wilma (both were accidents).
In this case a pole pig was lying in the street, completely torn loose from the pole and associated wiring. I didn't think of either of your ballast ideas, or I might have tried them. That was probably a good thing.
In this case a pole pig was lying in the street, completely torn loose from the pole and associated wiring. I didn't think of either of your ballast ideas, or I might have tried them. That was probably a good thing.
FYI, Angela Instruments has the big 75W SE transformers on sale.
Actually, they don't. I called them every day last week, they were closed. When I got someone on the phone today I was told that they had none of these transformers in stock, and they were no longer going to carry them.
Back to the drawing board.
I know that I have never been very practical but several hundred tubes in parallel would be a nightmare to maintain.
This reminds me of a guy that used to hang out on rec.audio.tubes years ago- Nick Sheldon.
He's made some insane amps,stuff with like 1000 6AU6 tubes in parallel,running at 800V,and cranking out 500W of audio..
Anybody know what ever happened to Nick?
I wonder if he hangs out here?
hey-Hey!!!,
I have a six-pack of these and four sockets... PP requires a substantial PS. Consider SE. Put that cathode current to use. In parallel it is ~23A. Run it through a dedicated coil on the OPT to cancell some of the DC in the plate circuit. I saw this done with the TL304 and it worked well.
SE Pentode would be able to run well over what an OPT could deliver, so why not draw a load line only a pentode would like: steep and through a 1k5V/250 mA operating point. 2k load perhaps?
cheers,
Douglas
I have a six-pack of these and four sockets... PP requires a substantial PS. Consider SE. Put that cathode current to use. In parallel it is ~23A. Run it through a dedicated coil on the OPT to cancell some of the DC in the plate circuit. I saw this done with the TL304 and it worked well.
SE Pentode would be able to run well over what an OPT could deliver, so why not draw a load line only a pentode would like: steep and through a 1k5V/250 mA operating point. 2k load perhaps?
cheers,
Douglas
Bandersnatch said:hey-Hey!!!,
I have a six-pack of these and four sockets... PP requires a substantial PS. Consider SE. Put that cathode current to use. In parallel it is ~23A. Run it through a dedicated coil on the OPT to cancell some of the DC in the plate circuit. I saw this done with the TL304 and it worked well.
SE Pentode would be able to run well over what an OPT could deliver, so why not draw a load line only a pentode would like: steep and through a 1k5V/250mA operating point. 2k load perhaps?
cheers,
Douglas
Hi, Douglas,
Can you show some proper circuit?
TTA
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