Without doubt the largest most effective 20M antennas were the 36 element
arrays used at W6KPC and OH8OS. Both these arrays were fully rotatable and
provided useful take-off angles. I personally viewed the arrays at both W6KPC
and OH80S. The W6KPC array was most elegant both mechanically and electrically
being mounted on a 200ft self supporting tower. The cross booms supporting the
collinear yagis had large sections of fiber glass rod breaking them up. The
OH8OS array used steel guy wires and continuous cross boom. It put out a good
signal but there were some question marks regarding interaction with the guys
and cross booms. Unfortunately both these antennas no longer exist. These were
truly monster 20M antennas that really worked. The reality is they only
provided a maximum of 3dB gain over the multi vertical non collinear stack. The
mechanical difficulty of the collinear multi stack array is a big price to pay
for 3dB, but it is a sight most pleasing to the eyes.
Ian VK3MO
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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