Original poster: "Rich & DJ" <rdj@xxxxxxxxxxxx>
Can a gap be added with a saw??? This is an old Jefferson and does not
have an EI core and no visible shunts.
Rich
Subject: Re: What do I do ?
Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
I suspect the problem is the NST with primary only. The inductance
would be high with little current going thru it if you removed the
secondary and didn't add any gap to the EI core. The current allowed
would be the same as the current thru a working NST of the same
design with the secondary opened (probably not much current). When
you added a secondary using 7 turns of 10 gauage (presumably
shorted), this allowed current to flow thru the primary.
Gerry R
>Original poster: "Rich & DJ" <rdj@xxxxxxxxxxxx>
>
>I am trying to get a transformer and ballast set up with just a
>spark gap for now. It is multi gap copper tube set up, 8 tubes
>total, 5 tubes in use @ .050 each .200 gap.
>The first ballast try was with a roll of 12 ga w/steel core and a
>NST transformer core with just the primary, when I ramped up the
>supply voltage it would barely fire when I got up to 95% on the
>voltage at the transformer input. I added 7 turns of 10ga for a
>secondary on the NST core, now I get good sparks at 60% voltage.
>Can any one tell me why ?
>I am using the roll of wire and NST core to limit my transformer to
>1.95Kva max. It is all trial and error at this end , should I add
>more turns on the NST secondary until I get null spot.
> I am getting actual 8 amp at the input of the transformer at 140v
> , max s/b 8 amp at 240v.
>I have a volt and amp meter at the transformer input.
>I think I would be better off with more volts and less amps or ????.
>
>Rich , from the middle of Missouri
>
>