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Old October 18th 05, 09:00 AM
David
 
Posts: n/a
Default Diameter of cable in coaxial Collinear antenna

Hi,

I am in the process of making a couple of 9dB Collinear antennas for 920
MHz.

I was wondering if the diameter of the coax is significant.

The design is simply 1/2 wavelength sections soldered centre to braid
with a 1/4 wave radiator at the top and a 1/4 wave sleeve choke and a
few ferrite toroid baluns at the bottom. The original design uses RG58
coax but I find this difficult to solder in short lengths and the
dielectric melts if the iron is left on too long. Instead I am using
RG174 PFTE dielectric. The Vp for both is still 0.66.

Thanks for any info

Regards

David