In a message dated 98-10-06 02:38:17 EDT, LOMAX1@prodigy.net writes:
> I have a question about mounting a Ham IV. I have two towers currently used
> for VHF/UHF. The method I've used to mount Ham IV's on those is by putting
> the rotor about 10 feet from the top and using a bearing at the top. With
> the rotor so far down I've never worried about axis stress. So far so good.
> Now, for this winter, I want to stick up a Cushcraft A4S. I don't have time
> or money for another tower this year. I do have another rotor with the
> attachment on the bottom that allows mounting on a post up to 2 inches
> (like a dupe of the top). Anybody have an idea whether putting the
> tribander right above the top of the rotor and mounting the rotor on a pipe
> would cause excessive stress on the rotor?
> Hopefully next spring I'll have more tower up for the time being will it
> work or am I asking for problems?
Go for it. All you have to do is de-rate the HamIV by 50%. The A4S is
small enough that you're not pushing the rotator capacity.
BTW, a T2X will take 3,000 ft.lbs. of horizontal stress before breaking.
The HamIV is smaller so might take 2,000 ft.lbs. or so itself.
Cheers, Steve K7LXC
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