Sinclair HD (heavy duty) folded-dipoles (various models - how many bays
and how much gain do you want?) have served well for decades around here.
Have also seen DB products arrays last similarly long lifespans in other
clubs/groups in the area.
One of those (dual-mast, 8-bay folded-dipole variety) only died when it
took a direct lightning strike, welded itself together at the joint
between the two masts, and had holes the size of dimes in it where the
lightning jumped from mast to tower. It was still working, but SWR was
crazy, and of course, radiation pattern was anything but "normal"... but
the repeater (with an isolator) was still on-air and usable.
Similar lightning blew fiberglass "stick" antennas taller than me into
so many tiny little white bits, that the remainder of the antenna other
than the bottom mount, fit nicely in a kitchen-sized garbage bag, for
one unlucky group out here. They were NOT on-air until they replaced
it, of course.
The only "killer" out here besides lightning... bad weatherproofing. Go
ALL OUT on weather-proofing connections. Have seen more instances of
water ingress killed the hardline feeding the antenna, than the antennas
themselves failing.
We also tend to have almost zero issues with heavy icing -- it's
typically too dry here -- but the few times I've seen it, the arrays
were so covered that system performance was actually degraded, but no
physical damage from the ice hanging from the antennas.
Ice FALLING from antennas/platforms/etc when the weather turned warmer
and started it melting... from ABOVE... has broken antennas... has
sliced hardline, etc.
Nate WY0X
On 3/8/2010 2:06 PM, Chuck Kelsey wrote:
Comprod makes an extra heavy-duty folded dipole array. It won't be cheap,
but then again you want it to survive for a long time. Tower work at that
elevation isn't cheap either.
Chuck
WB2EDV
----- Original Message -----
From: "camper161" <[email protected] <mailto:camper161%40yahoo.com>>
To: <[email protected]
<mailto:Repeater-Builder%40yahoogroups.com>>
Sent: Monday, March 08, 2010 3:50 PM
Subject: [Repeater-Builder] UHF repeater antenna recommendations
> Hello all, looking for amateur UHF repeater antenna recommendations.
The
> antenna will be over 700ft in the air, looking for something that will
> hold up in the wind and what ever Mother Nature might dish out.
