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[TowerTalk] Some assistance sought with newly acquired, used antenna bit

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Subject: [TowerTalk] Some assistance sought with newly acquired, used antenna bits.
From: wb4mnf@atl.org (Bob Duckworth)
Date: Mon, 28 Jul 1997 01:08:09 +0100
Hi-

Just finished a sweaty 6 hours with Marty AA4RM and my dad
gathereing up some antenna bits that we were given. I'm trying
to ID some of them and maybe find some manuals or specs of
some sort.

Antenna 1) appears to be a 3 ele dual band for 10 and 15m, It
has one set of traps per element and the elements are about 9'
to the moddle of the trap and 12 feet overall (at least the one I
measured). The elements sit on machined insulators which sit
on a rectangular cross section piece which is bolted to the boom.
No manufacturers name on it anywere. 

Antenna 2) is a 4ele quad but boom was not there so I'll have to
find one. spreaders are 13' long and my math says that 13 x 2**.5
is about 18' which make this a 20m jobby. Spiders are cast
aluminum in two pieces and 8 x screws go through one half of spider
and 4 spreaders to other half of spider. Looks like 2.5" boom is 
required but I've not measured it yet (just finished unloading the
pickup truck)

Antenna 3) looks like a 3 ele 40m Yagi. elements are about 26' long
and each has a coffee can sized plastic (coil?) in the middle. They
are insulated from the, what looks like 2.5 or 3" (I'll measure in the
morning) boom, which was not there (have to buy two booms or put
the 20m quad on the same boom as the 3 x 40m Yagi elements. I 
had asked about a triband quad on 40m boom a couple of weeks
back and the only discouraging word was that 15m was detuned.
Plan, if no discouraging argument works, is to put the 4 x 20m quad
and the 3 x 40m Yagi on the same boom at the top of a 72" crank up.
My neighbor has been bugging me to sign a waiver so he can put his
garage closer to my property than the city allows. This antenna will
overhang that garage in exchange ;-)

Antenna 4) A generic 5 ele 6m Yagi.

Now for the questions!

Does anyone recognize any of these antennas and maybe have
manuals. I don't need to get 'em working but it will make life a bit
easier. If no manuals I'll engineer some booms and ask for
tuning suggestions. Suspect resonating elements individually,
bolting her up, and then making it match is the usual way this
is done (all my antennas prior have been wire and tree)

I acquired 50' of 25G with this deal and an contemplating guying it
and putting the 6m and dual band yagi on the 25G. What's the
best height for that 6m? Should put the 10-15 at 50' and the
6m up as high as I can get it over this or should I stick the 6m at
50' and try to get the 10-15 up another 12 or so? I can probably
add one more section of 25G but after that, I'm out of guy room as 
there are a couple of 100' trees that limit siting options.

The tower for the big ants will be 72' crank up that appears to 
be a Tristao HD. I'll be using a house bracket at 23' and will be 
able to crank it down to 40' when not in use so it won't need guys. 

For anyone who has read this far, I'll describe taking down a 50'
piece of 25G with a 16' mast with another 16 or so feet of 2m 
collinear atop that).

First grab the 200' climbing rope. Climb the 26' to the roof peak.
throw enough of the rope to lower the tower around the chimney
and down to dad and Marty. Loop rope through the tower at 30' 
(I'm not climbing any higher as tower has one old piece of dacron
to a tree, a piece of polyester through the ridge end vent, and a
piece of heliax through the ridge end vent and that's it!) and tie a 
bowline. Cut dacron, climb down a bit, cut heliax and polyester
(Dad and Marty are pulling on climbing rope so she's pretty steady)
climb on down. Using the other end of the climbing rope as a tag
line and dads end as counter we start to pull the tower down.
Well, no one has lived in this house for 3 years and there is a big
Magnolia tree and a 40' holly making love to the tower. It comes 
over about 10 degrees. At this point we discover the flat plate base
really has a big spike on it. Marty and I grab a big pipe and pry the
base plate out of the ground. It's not bolted so we kick it off the 
bottom section. Some more pulling and the tower is at about 45
degrees and wedged in the middle of the holly at about 15' off the
ground. We unbolt the lowest section and pull it off. Still, the tower
won't budge. I've been encouraging them with, "this will only take
15 min more" for an hour! A couple of more heaves and we now the
top in the middle of another big holly at about 20'. We stop to
think. Next thing I know dad is in the holly at 20' yelling for the rope.
He used to be a forester but he's been retired for 10 years!. 
I throw him the rope, he ties it off, climbs down, and then all three
of us pull the top out of this second holly and slide the remaining
10' through the first holly. It's down! We have it apart and on the 
truck in less than 10 minutes. Took us about 2.5  hours but without
the trees would have been a 20 min job. Tomorrow, I'm taking a flat
bed wrecker to load up the crank up. Dad, Marty, and I could not 
lift it on to a trailer so it;s $75 for a machine to do it. I'll also take 
down the 6m Yagi. Have to bring a machete to clear a path through 
the jungle of vines at that end of the roof :-) Should be a simple 
unbole the U-bolts and lift the Yagi and mast out of the rotator.
If not, It will be pull the tag and hold the counter again. No trees at
this end though. 

I'll report dimensional details tomorrow or tue. 10-15 was a bit of
a bit of a bear too.

73,

-bob
wb4mnf

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