Martin,
I went up in my attic with a ruler and this is what I found for some feed
lines I made:
#24 stranded, silver plated teflon insulted, with about one twist per inch.
#26 , same type, about two twists per inch.
#28 solid, silver plated teflon insulated wire wrap wire about one twist
per inch plus a heat shrink tube about every two inches.
All are close spaced.
I also have about 1000' of #26 solid as above that would work too, or I
could use if for a near invisible antenna.
A good source of similar wires to above is eBay.
GL
73, Chas
At 10:58 AM 9/10/2005, Martin Gillen wrote:
Hi, Chuck.
I have a question about your feedline:
> I have made up some feedline using #28 teflon
insulated
> solid wire wrap wire held together with heat shrink
> tubing. The characteristic impedance is not
important and
> it is low loss. I measured some #26 twisted pair
once and
> it's impedance is about 180 ohms.
I know that coax can be looped around 5 times to
create
a balun near the dipole feedpoint. Can twisted pair
be looped around to create a balun also?
I don't see why not. You probably would want to use a plastic juice bottle
as a form, which I do anyway for coax.
Also, what
was
the distance between the twists? I'm interested in
making one to feed a dipole for my KX1 field ki
How can you measure that a balun is being effective?
Measure impedance with an impedance meter. the Z should be roughly 10
times the impedance of the feed line. Or else check antenna handbook and
use the dimensions they give. Note that the handbook is for coax, and a
higher impedance feed line will take more turns. Impedance is proportional
to N^2.
Thanks,
Martin.
[EMAIL PROTECTED]
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