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Re: Spark gap metals

Original poster: "Dr. Resonance" <resonance@xxxxxxxxxx>

Most heat sinks are made of aluminum. Aluminum does not have the conduction properties at RF frequencies that copper has. Alum. is not a good choice as the peak current in the primary circuit is limited by any part that has the most resistance, in this case, the aluminum.

Tungsten in 3/8 to 1/2 inch dia bonded to copper is an excellent choice.  We
use these in all of our coils up to 15 kVA, then go to 1 inch dia

You have to be concerned about the material (metal) as it effects your
energy transfer time especially if the metal is getting too hot.  The spark
gap will not quench (shut off) properly and the sec energy will flow back
into the pri circuit.  You want to keep the energy trapped in the sec with
no kickback into the primary (referred to as first or second notch energy

See Ritchie Burnett's website for a good primer on this subject.


Dr. Resonance

> > Why are ya'll so concerned about the metal your spark gaps are made of? > As long as your the metal has enough surface area( to radiate heat) and you > keep blowig air on it(like with a muffin man... I mean fan), it won't melt > and it would be fine. > You could even make a fine spark gap by replacing the copper pipes or > tungsten rods with old heat sinks from scrap computers.Besides, isn't > tungsten expensive? > Trust me, I may be new at this, but I can tell you that fan cooled heat > sinks or at least copper pipe(the longer the better) will do just as good, > if not better, than tungsten rods. > Also, the tungsten rods have less surface area than a copper pipe and > therefore more likely to get really hot, and even though tungsten cand > stand more heat, it doesn't need to as long as you cool it right. Tungsten > rods are just a waste of money and tungsten. > > Steven Steele > > >