Hi Gary,I've read Terry's paper listed many times. I've built several of these styles of multi-gap configurations. They all sucked! This is possibly the worst type of multi-gap configuration (in my experience).
These gaps are no comparison to a RQ large diameter multi-gap with high cfm. It's difficult for me to see the study as a quantifiable difference between single and multi-gap configurations. Peak voltage will be attained from the lowest loss gap. I guarantee my multi-gap will outperform both gaps shown in that particular study by a magnitude regarding losses. I've built both of "those" gaps Terry used and "know" their characteristics intimately. It's a good study of those two particular gaps, but I think the study is limited to only those two gaps.
This is why I am undecided. It may be that there is a difference between the two gap types as far as losses, but this particular study didn't do it for me. In hind site, I wish I had been more familiar with static gap characteristics at the time.
Take care, Bart Lau, Gary wrote:
It was after reading a paper published by Terry Fritz that I first came to the opinion that multi-segment gaps have higher losses despite offering better quenching. See http://www.hot-streamer.com/TeslaCoils/MyPapers/sgap/sgap.html. Perhaps I'm reading it wrong, but it looks to me like the peak secondary voltage is significantly higher in the single-gap cases when the coupling is in the region where we typically use it. And independent to that, I'm pretty sure that I've read that spark gaps are similar to zener diodes, in that they exhibit a near-fixed on-voltage independent of gap width. (This is where Bert Hickman usually chimes in...) There is no doubt that multi-gaps exhibit superior quenching over single-gaps, but contrary to what is often repeated on this list, quenching is not the primary determinant of gap performance. Regards, Gary Lau MA, USA-----Original Message----- From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On Behalf Of bartb Sent: Friday, February 22, 2008 9:31 PM To: Tesla Coil Mailing List Subject: Re: [TCML] Spark gap Hi Gary, I'm undecided on the single segment versus multi-segment gap losses. The only possibility of lower losses is "if" the arc resistance is lower in a single segment gap. The voltage drop should be the same for both assuming identical pipes diameters, surface, and total gap spacing. Take care, Bart Lau, Gary wrote:I'm similarly skeptical about a propeller gap's quenching. The only thing that Ican see superior quenching-wise is that the air flow over the gap may be better than in a cylinder gap. But if that was all you need for superior quenching, then an air-blast gap should be the best solution of all.I would think that a mult-segment cylinder gap is the best at actual quenching,due to the fact that being divided into multiple small arcs, they would be easier to cool and extinguish. But I also believe that multi-segment gaps exhibit higher losses (each gap represents a fixed voltage drop, and the more gaps in series, the greater the total gap voltage drop, and loss).The benefit of a propeller gap comes about in that it's a rotary gap. If it's a syncgap, it's superior because the bangs can be engineered to be consistent in size and timing, rather than the chaotic mode inherent in static gaps. If it's an async gap, it may be better than a static gap if the power supply is larger than what can be effectively handled with a static gap.Regards, Gary Lau MA, USA_______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla
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