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Hi guys
Recently i have found a problem with our 6db 473.575 mhz
repeater colinear antenna that is being used as a repeater antenna .From
brand new it seemed to work well but over time and especially on windy
days it will generate desense on our repeater(see previous posts on
fading desense) .We have other VHF/uhf antennas used on
other repeaters that exhibit the same problem for 3-5 years
where sometimes the weaker signals use to come good and clear and
then go bad with chopping and scratching .After a extremely windy
day we found that one of the antennas was faulty and wasn't even getting
out 5-10kms .After replacing it with a new antenna we have no desense
even when windy when the others are just showing signs of desense when
windy .So it seems that the antenna develop a bad joint over time
with the bending of the whip .I am wondering has anyone tried to make
the fiberglass more resistant to wind movement.possibly filling the tube
with foam or some other method .One manufacturer here had done the tube
in PVC instead of fiberglass
Thank You,
Ian Wells,
Kerinvale Comaudio,
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