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Re: Using HV COAX without stripping the shield

Original poster: "Mike" <induction@xxxxxxxxxxx>

Hi Ed,
I think I will do the same, though we have some RG-17 from work has a really large diameter plastic insulated center conductor for good HV and the conductor itself maybe as much as 10 AWG or 8 AWG.
We were scrapping some plate transformers from induction heaters because they were still good but taking up so much room, the original machines long taken down into parts in the shelves, one pair caught my eye, rare single phase at this power, so I asked and they let me load the truck and drive it over here. 30 Kva 200 to 250, single phase with a secondary of 10 kV, 3 amps. The company saved the other as stock
While I have interest in DRSSTC, I also like traditional coils and thinking of using this HV switching tube on the rectified supply rather than a gap.
One thing for sure, that transformer and it's weight, can stay put and I'll take the HV from it on cables. That is a dry transformer but is still way too heavy to haul around.
Mike


----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Friday, November 04, 2005 5:38 PM
Subject: Re: Using HV COAX without stripping the shield


Original poster: Esondrmn@xxxxxxx
I use RG213 for feed lines to my pole transformer. With the outer vinyl jacket and braided copper shield removed.

Ed Sonderman

In a message dated 11/3/2005 4:28:11 PM Pacific Standard Time, tesla@xxxxxxxxxx writes:
Original poster: "Mike" <induction@xxxxxxxxxxx>

Hi Gerry,
              The DR. is right, if you want to stop the voltage
gain in the coax, to stop the Blumlein effect, remove the shield.
Likely you are using RG8 because the inside conductor is jacketed in
fairly good/heavy plastic or these days, foam.
You cut away the shield, you've removed the ~ 29 pf per foot (forgot
the value but think that's it) and without the coaxial C you loose
the ring back power gain.
Google and check out Blumlein power supplies, nice way to 2 X or 4 X
or more, your pulse power. Used in some big pulse systems.
Termination Z is important on the line for full effect, also it is
possible to get reversal of polarity on a DC pumped system and you
can design that in or out.
Some systems have used a larger counterpoise around most of the
center line sides but not 360 degrees, I think U of Texas HV lab did
a lot of work in this area.
Very fast lines, though, if your looking for high current and voltage
gain. The networks you spoke about would need to take the ~ 300 amp
at 2 X voltage and sink it.
Cure sounds worse than the problem. Skin the coax else use it as a
power supply component.
Mike