[amsat-bb] Re: How to make phasing cable for 440 MHz Arrow II

Jeff Griffin kb2m at comcast.net
Sun Dec 2 16:39:05 PST 2007

 Wayne's  information copied from my website doesn't include the 
instructions on how I built my phasing harness. Lookup  callsign kb2m  on 
qrz.com, then  use the link to my (old hasn't been  updated in a long 
time )website, for the build procedure...

73 Jeff kb2m

----- Original Message ----- 
From: "Wayne Estes" <w9ae at charter.net>
To: <amsat-bb at amsat.org>
Sent: Sunday, December 02, 2007 2:27 PM
Subject: [amsat-bb] Re: How to make phasing cable for 440 MHz Arrow II

> Click the links below to see how KB2M modified the 7+7 Arrow 70cm yagi
> to be circular polarized.
> Hand-written diagram from W0OQC:
> http://i238.photobucket.com/albums/ff239/Wayne_Estes/Ham%20Radio/W0OQCHarnessdrawing.jpg
> Calculations to determine length of the two 70 Ohm matching cables and
> the 93 Ohm phasing cable:
> http://i238.photobucket.com/albums/ff239/Wayne_Estes/Ham%20Radio/W0OQCcalculations.jpg
> Photo of KB2M's finished wiring harness:
> http://i238.photobucket.com/albums/ff239/Wayne_Estes/Ham%20Radio/KB2MArrowmatchingharness.jpg
> Photo of KB2M's RHCP 7x7 Arrow yagi on the mast:
> http://i238.photobucket.com/albums/ff239/Wayne_Estes/Ham%20Radio/KB2MArrowonboom.jpg
> Note that this was done as a portable uplink antenna for AO40.  I can't
> think of any currently functioning ham satellites that would really need
> a RHCP 70cm antenna.
> The impedance matching cables are 3/4 wavelength long.  That makes the
> dimensional tolerances 1/3 as critical compared to making 1/4 wavelength
> cables.  The phasing cable is 1/4 wavelength long for obvious reasons.
> Also note that the dimensions should be measured from the center of the
> Tee to the end of the pin on the BNC connectors (connector and Tee
> contribute to the electrical length).
> Wayne Estes W9AE
> Oakland, Oregon, USA, CN83ik
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