Jerry,

I have experienced with baying arrays, which is horizontally split, but not 
vertically stacking them.  I can also tell you of a setup I had years ago.

First, as far as the two antennas.  You'll need a phasing kit which consists of 
a T-connector and two lengths of 75-ohm cable to match the two antennas as they 
will be fed in parallel.  I don't remember the length of the phasing cables, but 
you can get them already mead up as part of a separation kit from Cushcraft.

The other thing you need to consider is the phasing of your transmissions.  It 
used to be that the birds were left-hand circular polarized, if I remember 
correctly.  SSB is horizontal, and FM is vertical.  Which mode will you use the 
most?  If satellite, then you need to circularly polarize it if that is still 
necessary for the newer birds.  My experience if from Oscar 13 days.

A second consideration is that if you phase your two antennas, you will be 
narrowing the beam width.  That will mean that you might need to track them more 
precisely.

Some thirty years ago, a brilliant friend of mine, Wa8LMF, came up with the idea 
that I could put up a pair of 8-el HyGain two-meter beams and phase them either 
vertically, horizontally, or righthand or lefthand circular as my operating mode 
changed.  The way we did this was to put one beam up oriented with the elements 
going from upper left to lower right.  The lefthand beam on the horizontal boom 
had its elements going from upper right to lower left.  The two feedlines 
entered the shack and fed a T connector to the rig.  If I wanted to change the 
phasing, I inserted either a quarter wave in the left or right feedline for 
circular polarization if I recall, or a half-wave phasing line in one side to 
switch to horizontal polarization.

I do know this much.  If you worked FM and switched it to horizontal 
polarization, you had a considerable drop in signal strength.  And, when talking 
with an FM station, running circular polarization seemed to reduce the amount of 
picket fencing.

Steve, K8SP
----- Original Message ----- 
From: "Jerry Neufeld" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, May 21, 2007 2:21 PM
Subject: Stacked arrays on VHF & UHF


I have 2 CushCraft dual-band, 5-element yaggies for VHF & UHF that I'd like
to use for satellite work. Does anyone have any experience with stacked
arrays of this type? Any ideas where I might obtain accessible material on
how to optimize stacked, dual-band antennas? Any suggestions on this would
be much appreciated.

Also, I have a MFJ antenna analyzer, the 269 to be specific. Although this
analyzer provides for UHF measurements, it does not have a pick-off for RF
which I need for my MCount morse-code frequency reader. Anyone have any
ideas on how I might gain access to the RF output of the analyzer without
significantly influencing readings, especially for UHF?

Thanks to anyone who has advice on these matters.

Jerry  VE3QSO