I recently acquired a military surplus AB-577 48' mast system and I am
interested in figuring out whether it will safely hold a KLM 10-30-7 LPA
log periodic antenna. I've read several accounts of folks using the
AB-577 to support Cushcraft 402CDs, so it would seem that using an
AB-577 to support a 10-30-7LPA might be feasible.
Per the specification in the KLM assembly manual the 10-30-7 LPA has
30ft boom length, weighs 70lbs, and has a wind area of 8.3sqft. The
402CD by contrast has a 22.3ft boom length, weighs 44lbs, and has a wind
area of 6.4sqft.
Apart from the ability of the AB-577 to reliably support the 10-30-7
LPA, I am wondering about the rotator mounting scheme. The AB-577 lends
itself to installing the rotator in a "mast mounted" configuration and
most of the AB-577 installations I've scene pictures of show the rotator
mounted in this sort of configuration. This concerns me a little since
most rotators are derated significantly when operated in a mast mounted
configuration compared to when they are installed inside a tower with a
top-tube or thrust bearing to take the side load.
I would appreciate feedback from anyone who has some experience or
knowledge with regard to the aforementioned topics.
73, Mike W4EF...........
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