Spring antenna maintenance:
I am creating this topic as a place to put ideas, and plans for others in
the club in regard to antenna/tower maintenance for this spring.
Good weather is coming sooner than we might think, in fact, it appears to be
here now!
A few weeks ago, we had a few ?thunder busters? and extremely high winds
come thru our area and also up in NNY where my station
is located. I think it was late on a Wednesday night and into Thursday
morning that we had a big thunderstorm and the high winds. I had
been on the air via my remote internet connection to the camp on Wednesday
evening, and all was fine. I worked a few DX stations and
all of the equipment functioned fine, including the beam and the rotator. On
Thursday afternoon, I tried to log into the camp using my
logmein ignition program. This program logs me directly into the camp,
without having to type in the corresponding passwords each time
I access the camp computer. The small icon that comes up indicated that the
HLCC computer was off line and its last connection was on
Thursday AM at 4:20 AM. When this happens, one of two things went wrong. 1)
the power if off 2) the DSL modem is not communicating.
OK, for #1, I call the camp phone, if it keeps ringing, it indicates the
power is most likely off. If the answering machine picks up, the power is
on.
Good news, the answering machine picks up, there is power at the camp. On to
troubleshooting #2.
Seeing that I have had this remote station for a few years and have had
issues with the phone line and DSL modem in the past, the tech from
the local phone company did a stupid thing, he gave me his business cell
phone number and told me to call whenever I had a problem. Yep,
I called him on Thursday afternoon and informed him of the problem. He was
?busy?, very busy and was out on the road, repairing all of the
downed phone lines from the previous nights storm, but he said he would
check the DSL modem from the main switch when he got a chance.
Friday Am, I logged into the camp, and was successful, apparently he fixed
whatever was wrong with the connection or reset the DSL modem
>From the office, either way, all was OK, except:
There were no signals coming out of the Icom 746 Pro. I did have my typical
Skype connection, and it was working, but not hearing anything
>From the rig when I clicked on a CW DX spot. OH, OH, what?s wrong, did the
rig take a lightening hit? It seems more troubleshooting is needed.
I have two antenna ports on the rig, port #1 is for the HF bands, 160
dipole, 80 dipole, and the Pro67B beam (40 thru 10, but not 30 meters).
Port #2 is for 30 meters and it is an elevated ground plane antenna.
I click on a spot on 20 meters, and here nothing, then I switch to antenna
port #2, the 30 meter antenna and ?bingo?, there is the station that
was spotted. ?whew?, at least it appears the rig is ok and hearing fine, on
the 30 meter antenna. I wonder what happened? I guess it might be
the DX Engineering antenna switch that is mounted at the base of the tower,
maybe it took a hit or voltage spike or the interconnecting CAT 5
cable became unplugged or the cable got broken with a downed limb? Who
knows? On to more check outs of the equipment. Everything worked
fine, including the rotor controller and indicator. When I changed the band
to 80 or 160 meters, it appeared the noise floor came up, but still could
not hear any signals (this was during the day, so I expected no signals
there). Oh well, at least I have 30 meters working, and until I go up to the
camp,
I can still get on the air.
Monday, May 9th, I take a drive up to the camp and upon arrival, something
looks wrong immediately. The 160 inverted vee antenna is not attached
to the tower anymore, ½ of it is lying on the ground, the other half is
still up in the trees. The 80 meter dipole is also ½ down, the rope
supporting it
in the top of the pine tree had worn and broken. Those are not a big
problem, as they can be repaired easily and re installed. Next, I look at
the beam,
and it looks funny, leaning at sort of about a 15-20 degree angle,
definitely not correct. Seeing that it is up at 60 feet, out come the
binoculars for a close look.
AH ?####?, I could see the antenna was not connected to the mast where it
was originally installed (about 6 feet above the top of the tower and
thrust bearing), it was at the bottom of the mast and sitting on the thrust
bearing. I see the coax leading up the mast to the top 6 meter beam is
broken and the coax feeding the beam is broken off and the end of the coaxes
are exposed, not connected to anything. ?####? I say.
Oh well, down the hill I go and open up the camp for the summer, and NO
damage to the camp, that is good news. I turn on the computer and ??
What is this, the screen is upside down. J A quick text to K2MTH and he
gives me the command to get it back to normal. I am still wondering how that
happened?
This is where the title of this article comes in: Spring antenna maintenance
Anyway, up the hill to crank down the tower. The tower is a 51 foot crank up
which is guyed with phillystand at the top of the top and middle
sections. Before I cranked it down, I took a visual look (as best I could)
with my binoculars. The guys and cables all looked ok, so I crank it down,
insert a pipe between the tower section rungs to insure it will not slip and
come down any further. I did not want to have my feet on the rungs and have
it slip down and pinch my feet or worse. I called over to the neighbor and
asked him to be my safety man and watch me when I climbed.
These are important ?safety tips?. Never climb a crank up tower without
properly bracing the sections, and always have a second person present in
case
something goes wrong!!
Here is what I found to have gone wrong!
1) The bottom u bolt clamp on the mast to boom plate had snapped off
where the bolt protruded thru the plate. This is not good!
2) The top u bolt clamp had loosened and there was a space of about
3/8? between the boom to mast plate and the mast. This is not good!
3) The coaxes to both beams were stretched past their breaking point,
and both were broken (snapped). The cables were stretched, crushed, etc.
4) Due to these loose u bolt connections, the beam had been
freewheeling (or helicoptering as we say), it was not tightly attached to
the mast.
OK, back down the tower to the ground, I diagnosed the problems and now I
needed to get the proper tools, replacement parts, make up new coax, etc.
So I dismiss my safety guy and tell him I will call him a little later.
Luckily, I had all of the spare parts on hand in my shed next to the tower,
and thanks to John, W3OAB, who took the time during SSB Sweepstakes to do
a voltage and high current check on all of the extra coax cables at the
camp, I had a pretty good feeling that the coax I selected to replace to
crushed RF choke
and the coax leading back down the tower to the antenna switch were ?KNOWN?
good cables. I had to forget fixing the coax to the six meter beam, as it
was too far out of reach above the top of the tower to safely repair.
OK, I am ready, I call the safety guy, and back up the tower I go. Now
remember, I am just an older fellow, not as strong as I once was, but I hope
a bit wiser.
Trying to repair anything that is above your shoulders, with a 24 foot boom,
7 elements (2 of them 44 feet long), and pivoting on 2 planes (up/down &
Left/right) is almost insane. You all know me, that might be true. J
1st and foremost, there was NO WIND, absolutely calm, had there been any
wind, I could not have attempted the repair due to safety and the possible
unforeseen movement of that big beam. (I like my fingers just the way they
are, all in one piece and nothing crushed.) This is where a very useful tool
comes
into play ? a common ?C? clamp. Before I did any work on the tower, I put on
the c clamp above the boom to mast plate and drew the boom to mast
plate, tight to the mast and tightened it as tight as I could. This was
relatively easy, but I still had safety concerns, wind was going to start
blowing sometime soon,
and that C clamp was not going to hold anything that starts to move or twist
with any force!
I tightened the upper u bolt securely and felt a relief ?whew?, at least I
have stopped the side to side motion as it is now partially secured to the
mast. Then
I removed and replaced the bottom, broken and twisted U bolt with a brand
new one, and secured it to the mast. Both u bolts tight and secured to the
mast.
Due to not having the proper tools to raise the beam back up the mast, it
now sits about ¼? above the thrust bearing ( the toilet plunger that was
installed on top
of the thrust bearing (what is left of it) holds it up about ¼ inch), the
beam is 5-6 lower than before, but close enough.
That part of the repair is done. Next, I replaced the rf choke and connected
it to the driven element section(s), and installed the new coax and down the
tower
I go. All that is left is to crank up the tower. This is where I ?cursed? at
Rick, W1TY. You see Rick has a motorized winch which we used to use for this
purpose, but
apparently he took it home to sit in his garage instead of leaving in the
HLCC shed where it could be used. J Oh well, cranking up a tower is a pain
in the butt,
especially when it gets to almost the full extended level, you need to crank
it up full height and get those guys tight again. I finished the job, just
as the sun went
down over the trees and darkness appeared.
Job complete and I am one ?tired and aching puppy?, but happy, all is
repaired and all works.
Back to the topic Spring antenna maintenance:
Take care of your antennas/towers, check them and repair them as soon as you
can. I did not do this last year, and I paid for it. Luckily, that beam did
not end
up on the ground, as it surely would have, sooner or later (as loose as it
was, it would have been sooner).
Safety 1st and preventative maintenance should be priorities for all with
antennas/towers.
73 de Paul K2DB
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