Tungsten static gap

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Original poster: Gary VanderPutten <garyvp-at-earthlink-dot-net> 

RE; tungsten static gaps


This year I experimented with several different designs of tungsten gaps;
both used 3/8" tungsten balls silver soldered to 1/4" threaded brass rods.
Net investment of about $75. I used them to replace my RQ pipe gap which
required cleaning after five minutes. These were small coils that varied
from 250 to 750 watts.

The first design had seven electrodes inside a 3.5" plexiglass tube,
attached by 1/4 20 tapped holes in a circular fashion, ringing the tube,
with the balls inside the the tube. A rather delicate and exacting
undertaking.  However, it was easy to set the gaps by turning each threaded
rod.  Further adjustments was possible through tapping more  or less
electrodes. There was a high cfm muffin fan at one end. Observations: they
lasted longer than other static gaps, maybe by a few minutes. They did
develop a white oxide build up which had to be cleaned (easily done). The
fan is essential with this set up and it works well. I get more consistent
streamers, even on my little 12" x 2.5" coil.


The second design was just 3 open electrodes in series screwed into a plexi
block, with a fan at the side. Worked as well but got hotter.

Interestingly, some of the best performance was with just two electrodes - a
very simple gap. Very loud.

Overall, I like their look and ease of cleaning, but still not sure they are
worth the money. The lack of overall surface area is a problem and they do
get hot. I will experiment more this summer (that is when I coil).

Gary VanderPutten
The Urban Coiler