Turnstile question
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On Jun 17, 12:47 pm, "Jerry Martes" wrote:
I figured 1.8 inches for 1066 MHz. I wanted to build it into a pvc
pipe cap so there isn't much room to work. Also, am I correct to
assume the 1.8 is the total length, including what is stripped back to
make the connection?
Ralph
Hi Ralph
I dont know what your needs are for this Turnstile antenna, so my input
may be of no value. But, a Turnstile can be made to work by feeding
both
dipoles with one feed point. No phasing harness is needed. Make one
dipole a little short so it is capacitive and the other dipole a little
long
so it is inducvtive.
Jerry
The only problem with that is the antenna will still have basically a
dipole
pattern. I assume he is wanting the usual omni pattern with circular
polarization at the higher angles..
But maybe not... You need the phase line if you want a true omni
"turnstile"
pattern.
But saying that , I have used turnstiles with no line.. But usually on
80m..
And it does change the pattern a bit from the original single dipole,
but not
quite the same as using a phase line.
MK
Hi MK
I may have screwed up, but I think that a pair of dipoles on the same
plane, configured like a pair of non-symetrical Vs could be fed with one
feed point to produce a free space cardiod pattern. That would be one
short dipole and one one longer dipole fed in parallel.
Jerry
Jerry
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