In a message dated 5/28/01 8:38:41 AM Pacific Daylight Time, w7ti@jps.net
writes:
<< On Sat, 26 May 2001 22:19:38 -0700, Stan or Patricia Griffiths wrote:
>For most of
>us, it means more than just telescoping the elements out a
>little farther. I doubt there is enough spare aluminum in
>your current beam to do this.
_________________________________________________________
To go from 7.0 to 6.9 MHz, just add approximately 5.5 inches to the end of
each
element. It does not have to be aluminum tubing, just a piece of stiff wire
would do fine.
73, Bill W7TI
>>
Bill you are right. But the wire will have to be a fair amount longer than
the equivalent tubing length it connects to due to it's small diameter. I'd
make a big loop as if you don't, it could spit fire. A commerical BC AM SW
station found that out with small diameter tubing at the end of a vertical.
A ground keeper came in and told them "there was on fire coming off the end
of the vertical." They came up with a special loop for the tips that cured
the problem and it works. I had an antenna with voltage so high it cracked
insulators at 250W. This special loop cooled it completely. If the yagi at
the SW BC Station in SA had this loop on the elemetn tips at the high
altitude there, Moore's quad wouldn't have seen the light of day.
The Station Mgr of the SW station told me "they have a way to test antenna
tips for break down. If they can play Stars & Stripes Forever with no fire
on the end of the antenna tips, it will take anything else of the day." k7gco
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