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Old October 17th 06, 03:27 PM posted to rec.radio.amateur.antenna
Bob Bob Bob Bob is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 32
Default how to eliminate mechanical resonance?

Take a sheet of rubber (say 3-5mm thick) maybe 150mm long and the
circumference of the element wide. Make 3 equally spaced cuts 70% of the
distance of the long dimension. It will now look like a 4 fingered hand
shape!

Using a hose clamp tie this rubber sheet around the uncut end around the
elements at some convenient place. The idea being to damp mech
oscillation. Maybe 1/3 the way down each element but I haven't exactly
thought about where the best place would be.

It may slightly detune the antenna but I haven't thought that through
either!

Cheers Bob VK2YQA


wrote:

Hello all,
I build one year ago an 8 element 50 MHz yagi. Boom is made with 50 mm
square aluminum tubing with