It has been my experience that disconnecting everything and putting the
plugs on the floor works.
73 Hardy N7RT
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of W5GN
Sent: Saturday, May 14, 2016 12:13 PM
To: 'towertalk'
Subject: [TowerTalk] Lightning Damage, Crane used to replace Orion
Positioner
About two weeks ago, we had an extremely close lightning strike that surged
our AC voltage to about 6000V (estimate based on ¼ inch
between the two arc burns on the shell of the plastic AC plug to the chassis
screw on the Orion 2800 Control Box), even though
all circuits have commercial surge protectors that were installed when the
office/radio wing was built in 1984.
But I did NOT have a UPS between the wall and the radio equipment; none of
the computer equipment in the other corner that is
behind a UPS was not touched by this surge.
The surge took out that Orion 2800 rotor control box, and the motor windings
in the positioner was now an open circuit.
The surge also took out the Astron 30 Amp supply, and its 12V output surge
took out the transmit side of the ICOM 756PROII.
I sent it to Icom repair in St. Joseph, MI, on a Tuesday, and they had
finished the repairs and were ready to ship on Tuesday
when I called them on this past Monday, and it arrived yesterday, Friday.
$192 - $140 Service, $23 for parts.
They replaced the defective IC151 and D131 in RF unit, and the CI-V remote
port that I didn?t know was burned,
and replaced Q5771 Q25, D22, D23, clock battery BT3501 and, unrelated to the
surge damage, replaced R1 on the phone
board which had failed a while back and caused loss of one audio channel.
That 12V surge also took out the 20 meter position of the Array Solutions
Six Pack, and the MicroKeyer II.
The UST HDBX-72 tower is normally nearly retracted, with the top of the
tower at 32 feet, with the Cal AV 2-el Forty there,
and the OB16-3 18 feet higher. My first tower climber volunteer observed
the first problem. The tower needed
to be raised about 10 feet to get the positioner clear of the next lower
tower section so it could be removed.
But the electrical control has not worked for some time, and since I had not
intended to raise the tower,
and since I added the complexity of the (useless IMO) Remote Control, we
gave up on fixing that problem,
and instead used a screw driver as a lever and rotated the drive shaft to
raise the tower the 10 feet,
alternating two of us for about 20 minutes.
My professional climber could have replaced the Positioner in the tower in
harness on the tower, but since
the LMR400ULTRAFLEX was now 13 years old, I elected to bring a crane so they
could be replaced, and because
it?s a lot easier on the climber!
In 2003, we had a 160 ton crane (pics at www.mxg.com <http://www.mxg.com> ,
lower left) because we had the old EzWAY Tower further back that
had to be removed first; that day?s crane cost was $700.
When I called Davis Crane, I found that a city permit to close the street
would be required, two Dallas (off-duty)
policeman that we would pay $240 each for were required, that the crane
could not be here on Friday, our garbage pickup day,
per city rules, and because our normal residential street once had a bus
line, it was classified somehow higher as
needing to be clear by 3:30 for ?rush hour?. He also said the crane would
leave around 8am, about a half hour away,
and it would take an hour to setup, and also it would take nearly an hour to
shut down and be gone by 3:30.
And I had to deliver 42 ?Notice of Street Closure? to the folks who lived on
the two streets and backed up to the
alley exit that would be closed that day, record their addresses and deliver
back to Davis to get the permit.
The city had put out the Detour Signs on Wednesday, by the curb.
I had ordered 2x LMR400UF, Rotor, and RG8X Pulse cables in 200 foot lengths
from Joel, at RFConnection.
When the LMR400UF arrived, I decided to confirm its length by weighing on
the shipping scale,
and found the weight of the LMR400UF was .068 Pounds/Foot, so 200 feet
should be 13.6 pounds,
but the scale displayed only 7.7, so there must be only 100 feet of coax.
Only after wasting Joel?s time,
for him to confirm the actual shipping weight was 38 pounds, did I apologize
for the egg on
my face, as my scale was displaying KiloGrams, not pounds. Wednesday
afternoon we removed the old cables
from the shack to the base of the tower, made up the new cables, and ran
them from the shack also to
the base of the tower.
Thursday the crane and officer arrived about the same time, a little before
9, and the officer pulled the
detour signs to block both lanes, and then sat in his surburban pretty much
the rest of the day.
The crane arrived, and we then waited nearly an hour while they called back
to get the man basket that had been
ordered but not put on the order form. Then we waited another 45 minutes
for their mechanic to arrive to
find the short in the winch?s terminal block that was water-exposed and
intermittent.
Work proceeded smoothly for the coax removal for the OB16-3 which is now at
60 feet on the 24 foot mast and
then the Cal-AV 2el 40 is at 42 feet.
Work was somewhat slower when it came to raising the mast so the positioner
could be slipped out;
previously, you could get two winches, so one can hold the basket while the
second is used to
raise mast those couple of inches needed, but OSHA rules now prohibit two
winches, so the crane had to
swap the basket with a strap to lift, while the climber clipped in, and then
go back and get the basket,
several times. And similarly, since both antenna?s feed point is some
distance from the mast, and
with those 16 elements on top, only about 2 feet apart, the crane operator
took lots of time to reposition
out and then back in without taking off elements to move along the boom with
the coax.
Around 1pm, a city of Dallas inspector showed up and halted work because the
permit required two policeman,
which I had expected and was on the order also, but only one had been
ordered, apparently, by Davis Crane,
maybe, but this was a Keystone Cop discussion between the Davis guy, the
cop, and the (REALLY NASTY) inspector,
who finally relented, saying, well I?m not stopping your work now, got in
his vehicle and drove away.
Earlier he had told me that the reason the policemen were there was NOT for
traffic control, the signs did that.
They were there in case the crane tipped over so they could call for help!.
So both the cop and the Davis guy were worried about him coming back and
giving us grief over that 3:30 limit,
and there can be serious fines involved, so my tower guy got 5 minute
warnings for the last half hour,
and connected the last critical wire at 3:32. The crane shutdown took only
10 minutes, and he moved the crane
so it was now parked and only blocking one lane, and then sat there 45
minutes, waiting for the electrican to
return to now repair the crane storage mechanism ? the crane was completely
collapsed, but that whole unit
was stuck about 3 feet above it?s cradle.
So that lost time really hurt; it still took three more hours on Friday for
him to climb and strap in and
finish building and sealing the Bud box with the terminal block for the
positioner, tie wrapping and taping
the cable bundles, and finishing those details.
I had purchased the new Orion 2800 positioner only, because last year, for
the first time, I actually
won something of value at the Contest Dinner, when I got a Green Heron
controller. When we went to
setup that box, we made some stupid error, but were very pleased when Jeff
answered his phone and
he walked us thru to correct our error. Just love that knob to point the
beams.
The cost of this crane was $2440.
73
Barry, W5GN
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