STACKING ??? HELP
Sun, 9 Feb 1997 17:36:24 -0500 (EST)
In a message dated 97-02-09 16:37:26 EST, you write:
>KT34XA AT 90FT.
>ANOTHER KT34XA 33FT. DOWN ON THE TOWER (57FT FROM GROUND)
>DUNESTAR WX0B STACK MATCH
>BOTH POINTED AT EU
>I DID SOME SIGNAL REPORTS IN TO EU ON 20MTRS. AND WAS NOT REAL HAPPY WITH
>THE FINDINGS. THE HIGH BEAM ALWAYS HAD A MIN. OF 1-2 S UNITS BETTER SIGNAL
>THE TWO OF THE STACKED. SAME FINGINGS ON 15MTRS.
33 feet is pretty close for 20 meters. Did you model the stacking?
I'd recommend some computer homework first and see where you are.
One thing that can screw you up totally is to have the antennas out of
phase. Make sure that the center conductor and shield are oriented the same
for both antennas.
>NOW TWO OF THE GUY WIRES ARE CLOSE THE THE FRONT END OF THE LOW BEAM.
>THE GUYS ARE INSULATED FROM TOWER.
This is a topic of some debate but my experience has been that the
insulated guywires still have a negative effect on antennas that look through
The chief culprit IMO is the phasing. When they're working properly,
you'll understand why people like stacks of antennas - it definitely makes a
If the phasing is okay, I'd move the bottom antenna farther away from
the top one and closer to the ground. Distance from ground isn't as critical
as distance between antennas.
73 and GL, Steve K7LXC
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