[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: More DRSSTC fun!

Original poster: Steve Conner <steve@xxxxxxxxxxxx>

At 17:47 22/05/05 -0600, you wrote:

I see you coil is working well ;-)) Apparently you have not even blown anything up yet!!

Still on my first set of bricklets :))) I must have almost a whole minute of runtime by now, how's that for industrial reliability ;-)


You want the voltage between the primary and secondary area to be say 240 V not 10,000 volts.

Actually I have it wired the wrong way round, the top turn of the primary is hot with 10,000v from the tank capacitor. I figured that the secondary would be about 50kV there anyway so another 10kV wouldn't make much difference. But maybe it makes all the difference!


It might be a tuning problem too.... Worst, it could be the driver circuit loosing sync or something.

The scope traces seem fine and there is no evidence of the PLL messing up. There just doesn't seem to be much output on the lower pole considering the level of primary current and the voltage that builds up at the secondary base. The upper one works much better.


You can always raise the secondary in any case.

I think I will have to if I want to explore any of the more extreme tunings that Steve Ward uses. The tuning I'm using just now is pretty tame and I've not seen the primary current get above say 200A. It rings up in the first 50-100us and just sits steady till the end of the burst.

On Steve's coils the primary and secondary are tuned way out to build up a stupid level of primary current, then when the streamer forms, it snaps into tune and lets go the stored energy almost all at once. That whiplash effect would probably cause a mega flashover with the current setup.




Be interesting to see what the fix is, but it will probably be easy once you find it. Hopefully, the latchup problem will disappear with the corona.

I think using less plastic and more air would have been a good fix. The plastic has a higher dielectric constant so it concentrates the field into the remaining air gap.


Steve