Andrew and all, David is absolutely right.The root cause is that your tank capacitor and gap electrodes are too small for the current delivered by your HV power source. After the first "bang", the high power supply current recharges your tank cap too rapidly - before the tips of your electrodes can cool below incandescence. When the tank cap voltage rises too rapidly, the gap re-fires at a relatively low reignition voltage. If the electrode tips are still incandescent (from the previous firing), they readily emit free electrons (thermionic emission) into the gap, causing it to reignite at a much lower low voltage compared to if they were cooler.
The result is that your tank cap never has a chance to recharge to anything near full voltage before the gap re-fires. The gap develops a fiery appearance that quickly oxidizes/melts up your gap electrodes. Since the "effective bang size" declines substantially, your coil's output drops catastrophically - sometimes to virtually nothing!
Bert -- Bert Hickman Stoneridge Engineering http://www.capturedlightning.com *********************************************************************** World's source for "Captured Lightning" Lichtenberg Figure sculptures, magnetically "shrunken" coins, and scarce/out of print technical books *********************************************************************** David Dean wrote:
On Friday, March 29, 2013 09:26:22 AM Andrew Webster wrote:I swung by the local metal recycling facility yesterday and got some .25 inch tungsten rod I'll have to cut down and ordered a new sheet of phenolic. I'll have the new gap up soon.So maybe it takes twice as many "few seconds" to melt the tungsten as the brass. In order to "cure" the power arc you need to reduce the power (via suitable ballast) to a level the coil and gap can process. IMHO _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________ Tesla mailing list Tesla@xxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla