Damn lightning - there should be a law against it g. I saw your tower
raising epic on one of your webpages, and was very impressed with it -
would love that at my QTH, but am currently renting, and as I move
around very frequently with work (10 times in the last 13 years), a
tower would need to be very portable, and the hassles of doing something
like your setup every 18 months or so would really **** me off.
Currently I use a variety of wire antennas, and a number of poles to get
the verticals at about the 25 foot level. Certainly no powerhouse, but
able to get to pretty much wherever I want to (within reason of course).
Matt
Roger Halstead wrote in message
...
On Wed, 31 Dec 2003 17:44:21 +1100, "Matt"
wrote:
Nasty, but unusual - in 20 years of playing with radios, I have not
had
the problem that you have mentioned, but then again, I guess that I
don't have a huge lightening rod of a tower that you do (bloody nice
BTW). For the average user, the procedures I have mentioned will
suffice 99.99% of the time (looks anxiously up into the sky to check
for
lighteningg).
The hit was on the old tower, but that still put the base of the
repeater antenna at 90 feet, so the top would have been close to 112
feet. It hasn't been up in years.
The surprising thing is the bolt took out the 7/8" Heliax about 30
feet down from the top of the tower. I did lose the front end out of
one solid state 2-meter rig, but that was it. Everything else was
still working including the one with the water running out.
The current tower and even the old were getting hit about three times
a year, but there hasn't been any damage in a while.
My neighbor was looking across his back yard this past summer when the
top took a direct hit. It apparently really impressed him. Now the
neighbors really believe me when I tell them it's the neighborhood
lightening rod:-)). OTOH I was out by the end of the driveway
talking to the neighbor across the road with a storm in the distance.
A strong bolt hit the power pole about 30 feet from us. We both
decided we needed to be some where else... Quickly.
Currently my biggest concern from lightening is the computer network.
It's a 130 foot run to the shop and 25 feet in the other direction to
my wife's computer. The pone line comes in underground, but it
doesn't take much induced current to cost many dollars.
So far, I haven't had any problems with the satellite dishes and
feeds, but I have lost the antenna mounted preamp to the top UHF TV
antenna. Course that may have been due to 2-meters instead of
lightening.:-))
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair?)
www.rogerhalstead.com
Matt
Roger Halstead wrote in message
.. .
On Wed, 31 Dec 2003 16:08:10 +1100, "Matt"
wrote:
As with all of my external cable connections (excluding mobile
installs), I use good quality plugs that physically screw
together.
The
when I am finished, I use self amalgamating tape (costs about $20
Aust
per roll) which provides a weatherproof seal around the
connection -
have cut the tape off plugs which I have done ten or more years
previously to find them as dry as the day I put them together. On
top
of the self amalgamating tape, I use the normal electrical tape to
give
the birds something to peck at before they reach the self
amalgamating
tape (bloody cockies can be ferocious with antennas and coaxial
cable
here).
I believe that the only way that coax is going to become water
effected
is if it directly exposed to water (i.e. rain), and once you have
put
the connector on the end of the cable, screwed it into the antenna
and
taped it up, the chances of water getting into it are very remote
(bar
the outer layer being cracked, cut or abraded). In my opinion,
pressurising the cable is not something that is needed for the
average
hobbyist.
It only took one lightening strike to change my mind about
waterproofing 9913.
I used coax seal and taped over that. The tower took a hit that
removed every single bit of tape and coax seal from up there. I
found
the coax seal on the ground. It looked like some one had cut down
one
side and peeled it off. Then cut it so it looked like one of those
pieces of expanded metal. It even removed the silver plating from
the
connectors.
15 minutes after the lightening strike I had water running out of
my
2-meter rig.
I ordered 1500 feet of LMR 400 right soon after.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair?)
www.rogerhalstead.com
Matt
Dave Woolf wrote in message
...
Just wonder what other's might do to keep moisture
from getting into the semi-hollow 9913 type low
loss coax. It would seem inevitiable with changes
in temperature and pressure that moist air would
eventually work its way into the coax and then
condense.
I had a fellow ham that took the precaution of
pressurizing this type of coax to maintain
positive pressure and keep out outside air.
Seemed like a lot of effort but maybe it is necessary.
I have tried to seal the ends of the coax with silicone
sealant but I am not really sure that this has been
effective in the long term.
What do others do? What has been your experience?
Dave - K8RSP
(to reply to me directly remove NOSPAM from above
address)