Re: NST Pulse Voltage- getting pole pigs

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Steve Conner <steve@xxxxxxxxxxxx>


> the chokes only lasted for about 10 mins before the insulation burnt.

Oh :( Mine have been OK. I modified them by tying one of the output 
terminals to the core, and jamming a piece of plastic in to insulate 
the wire that comes out from the inner layer of the winding.


> The only problem with the inductive charger is that you limit the 
> bang rate due to the changing reactance at different bang rates

If you use a de-Qing diode, the tank capacitor always charges to 
twice the DC link voltage no matter what the breakrate. See Richie 
Burnett's DC charging theory page.

I had trouble with power arcing on the rotary gap of my DC coil. I 
got some vicious trailing arcs that went almost a full 360' making 
the gap look like a catherine wheel. They would short the power 
supply and blow the mains fuse. But it went away at higher breakrates 
(200+ bps) and provided I got the gap motor up to speed before 
ramping up the HV supply all was well.


> Does 4K look reasonable for a pole pig?

4K what? Ohms? VA? lbs? Or worst of all, money :-O

4K GBP seems believable for a brand new piggy straight from the 
manufacturer. But second-hand ones (11kV, 5-15kVA) should be a lot 
less if you can find them. If you are lookng for big transformers, 
try subscribing to the TCBOUK mailing list

http://groups.yahoo.com/group/tcbouklist/

and asking if anyone has one for sale. As far as I know, all the UK 
coilers with access to pigs are on the list.

Steve Conner