I wouldn't add extra guy sets to the stock AB-577 with the 75' extension kit
(follow the 'LXC Directive!) When properly anchored and tensioned, the guys
that come with the mast will make it quite stiff and sturdy. These things
were used to support relatively large microwave dishes, after all. The only
time it's going to act like a noodle is when you're raising the mast, and
extra guys sets won't help in that case.
However, there's a procedure in the manual that will minimize the noodle
effect when raising the mast. It requires a man at each guy anchor and one
in the middle to raise the mast. It's best to have a fifth man acting as
coordinator. Basically, the men on the guys work together to keep the mast
vertical while it's being raised. They pay out just enough guy cable to let
the mast rise, but not so much that it starts to tilt more than a few inches
in any direction. It's possible to do this with fewer people (I've done it
with two) but you have to run from anchor to anchor paying out no more than
a few inches of cable at a time. It's a tedious process, but it works.
Personally, I'd opt for having a large crew -- things will go much faster.
Do you have a manual? If not, I strongly urge you to get a copy and not to
raise the mast until you have read and understood it thoroughly.
I wouldn't necessarily recommend this to anyone else, but I've raised a 4-el
SteppIR on a 75' AB-577. That antenna has a 32' boom, weighs well over 100
lbs and has a windload of about 10 sq feet. I had the antenna up for about
two years, using the stock 3-foot screw-in guy anchors. It was kinda scary
raising the thing (especially since there were only two of us doing it), but
we took our time and got the job done. No one seems to know the official
windload capacity of an AB-577, but the owner of Ontario Surplus told me
that 10 sq ft and 100 lbs was probably the upper limit. Personally, I'm not
anxious to put that much windload on an AB-577 again!
73, Dick WC1M
> -----Original Message-----
> From: Robert West [mailto:robert.west@eatmoresoap.com]
> Sent: Tuesday, April 28, 2009 10:23 PM
> To: k4tmc@aol.com; towertalk@contesting.com
> Subject: Re: [TowerTalk] AB-577 Surface Guy Anchors?
>
> 50 pounds on top I estimate. I didn't think about vehicles because this
> would be up for 4 or 5 days for a ham fest memorial day weekend. I got
this
> tower from an old ham who said he was getting too old to handle the thing.
> He had it up 5 years straight but he had it bracketed to the side of his
> house as well as the guys. We have the thing pretty much refurbished and
> looking good but as someone mentioned, it would be like a noodle even with
> guys that are with it. Has anyone had any experience in adding additional
> guys to this setup and would it make any difference to the stability or
> would it just add to the complications?
>
> -----Original Message-----
> From: k4tmc@aol.com [mailto:k4tmc@aol.com]
> Sent: Sunday, April 26, 2009 1:39 PM
> To: robert.west@eatmoresoap.com; towertalk@contesting.com
> Subject: Re: [TowerTalk] AB-577 Surface Guy Anchors?
>
> Robert,
>
> You did not indicate what will be at the top of the 75 ft AB577 mast.
> That will also have some bearing on how strong your guy point should be.
>
> Since you are on a parking lot type area, I assume that you can park
> vehicles on the surface. If so, then make a frame assembly that can be
> held down by the weight of a car/truck by driving a wheel on top of the
> assembly. Or, if you have vehicles with towing capabilities, then use
> the tow hitch assembly to attach guy lines. If they can handle a
> 3000lb boat, then they will handle the 577 mast easily.
>
> Oh, be sure to have the vehicle owners sign waivers relative to any
> damage caused by a falling mast.
>
> 73,
> Henry - K4TMC
>
>
>
>
> -----Original Message-----
> From: Robert West <robert.west@eatmoresoap.com>
> To: towertalk@contesting.com
> Sent: Sun, 26 Apr 2009 1:23 pm
> Subject: [TowerTalk] AB-577 Surface Guy Anchors?
>
> Hello all. I have acquired one of the AB-577 mast kits with the
> extension
> to 75'. I am needing to erect this on a parking lot type area,
> asphalt.
> We are not permitted to penetrate the asphalt so we need to fabricate a
> method to anchor the guys on the surface, such as with weights. I've
> seen a
> method that is used for a non-penetrating mount for large dish antennas
> on
> roofs that consist of steel angle iron welded in a frame and filled with
> concrete cinder blocks bolted together with threaded rod so that they
> don't
> move. Works well in that usage but how about something similar for a
> guy
> anchor? This is a temporary thing so it would need to be easily
> removed.
> But my real question is, besides any other ideas, how heavy would I
> need to
> make these 3 weights? The height is 75' and is rated for 75mph wind.
> Would
> feel safer if the guy anchors could give us 100mph just to be on the
> safe
> side. Maybe a layer or 2 of block and then sandbags?
>
>
>
> Any ideas?
>
> _______________________________________________
>
>
>
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>
>
>
>
>
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