[BC] More thoughts about AM transmitter lightning

[RichardBJohnson at comcast.net]

They would be called "no-arc" gaps because, if they were
in a nice clean vacuum, they wouldn't arc until the spacing was
so small that dendrites grew out of the metal and shorted.

The resulting arc would clear the short.

On the other hand, we do have gas-gaps. TELCO uses
them all over the world. There are two in every TELCO box
on every house with a telephone.

However, RF will fire them off! If you used a high work-function
gas like dry nitrogen so that RF wouldn't fire them, they will
certainly explode when 3,000 joules of lightning power sets
them off. Ball-gaps can take that, something enclosed
with its internal gas instantly heated to thousands of degrees,
will not be observed intact again.

--
Cheers,
Richard B. Johnson
Read about my book
http://www.LymanSchool.org


 -------------- Original message ----------------------
From: nakayle at gmail.com
>  It seems to me there is a great market for  "vacuum ball gaps"- made
> similar to vacuum variable capacitors.  The problem with conventional ball
> gaps is that they are exposed to all sorts of varying conditions- rain,
> dirt, insects, paint, etc so they must be set wide enough for the RF not arc
> with even in the most adverse weather like heavy rain.  If the balls were
> enclosed in a sealed vacuum container they would be in a stable dry
> environment and could always operated at the optimum spacing.
> 
>  - Nat Kayle