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Old February 1st 04, 06:49 PM
Jimmy
 
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Depends on the mechanical rigidity ogf the materials. I have built them from
brazing rods that definitly needed the insulating spacers to keep them
stable. If the OP built something like the copper cactus then he should not
need them.

" Stephen Cowell" wrote in message
. com...

"Jimmy" wrote in message
. com...
In the plan I have for one it calls for a piece of fiberglass rod,

others
bakelite. to keep the two sections of the J at the right sepration.


Are we talking regular J, or Super J here? The
antenna you're describing is a Super, a colinear
array with the middle phasing section. In a normal
J-pole, there is no insulator needed.

Here's a confusing point from the original post...


I recently built a two meter j-pole.In the plan,I saw no mention of pvc
use.Yet,I had to place a piece of pvc between the two uprights to get
the swr to fall.Is there something I missed?
/

Is the pipe used in an insulator fashion, or
is it used to spread the Q-section? I believe
it's the latter... if so, the newbie can just bend
or re-solder the pole so the spacing's correct.

And if the newbie is describing a 300ohm
twinlead J-pole, then I give up.

Somtimes
mechanical rigidity is enough, for one like the latter search for

"copper
cactus".


A thing of beauty... I've got a nice copper
J for six that I'm considering converting to
the saguaro configuration.
__
Steve
KI5YG
.