I'll second Bob's comment about the bubble level. It's useless. The rest of
his comments are spot-on in my experience. I didn't mention earlier that I
have three AB-577s, one with the extension kit, and the two 50-footers have
been up with small HF beams for about eight years with only minor incidents
(a couple of broken guy wire clips.)
73, Dick WC1M
From: Bob Allen [mailto:mcamp@gmavt.net]
Sent: Wednesday, April 29, 2009 6:42 AM
To: wc1m@msn.com
Cc: 'Robert West'; k4tmc@aol.com; towertalk@contesting.com
Subject: Re: [TowerTalk] AB-577 Surface Guy Anchors?
I'll chime in here as I have used AB577 towers for Field Day for the last 8
or 9 years.
Read the manual and then read it again!!
Use 7 people to erect this if you can, 3 holding the upper guys and keeping
it straight, two spotting the tower for straightness and two putting it up.
You can have one person crank it up and one person spot but they run around
a lot.
The spec. manual says that the test spec for the tower is the guys tensioned
to 150 lbs each and there are four guys on each side so the 450 lb. drum is
a bit shy, use the vehicles and disable them or use something that weighs a
ton or more, large cement blocks, 4 drums (disclaimer time: I have not
calculated the force on the guys for the max. rated wind speed (75 mph and
1/2" ice) so 1 ton is a guess pure and simple).
The brake is rated for 500 lbs but this is way above what should be on this
as even 100 lbs is probably pushing it. We put around 65-75 lbs. on ours.
Make sure you get the frame plumb using a good level before raising it, not
that idiot bubble on the frame.
Make sure that the frame is firmly shimmed at the bottom if the ground is
not level
As you raise it see if the tube is bearing hard against any of the rubber
rollers as this is a sign that the crew isn't keeping it straight.
The winch will give you an idea as to how it is going, if it starts to bind
take a look around.
We never used our extension kit so this is all based on the 50' setup
except for the comment about having 4 guys.
Our towers withstood a 50 mph squall that knocked tree limbs on the guys and
they were rock solid.
Look here for our FD setup, it must work, we were the #1 2A station in
1999,2000,2006 and 2008, yeah I know it is not a contest :)
http://www.ranv.org/fdrpt.html
Have fun and good luck
Bob
KB1FRW
73
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