Gary, all I can tell you is my practical experience. Have a Hy-Gain
402BA (2 Ele 40) that the previous owner tightened the element to boom
set screws too tight crushing the boom and stressing it so hard it broke
through the boom wall (1/4" hole at first). So, once in awhile it gets
blown out of horizontal. I never noticed any practical degradation of rx
ot tx signal. Just climb the mast (12' above the tower) twist the boom
to mast bracket and straighten the dern thing...a royal pain. Takes
about 20 minutes to do and 4 hours to get the nerve to climb the mast.
The 402BA electrically connects the reflector to the boom through a
shorting wire. If that comes loose, it may degrade performance. Planning
on changing the boom next month to elimiante this problem. Now, might I
suggest that the reason for your poor performance is that an electical
connection came loose in the storm. Go get the nerve and straighten it
out!
Good Luck and 73,
Bob K3GT
Gary E. Jones, Ph.D. wrote:
>
> I tried this several days ago and got not a single response. That tells me
> either that my question was incredibly stupid, or incredibly insightful. It
> seems neither to me, so I will try again and see if I can get some
> information.
>
> A hurricane blew the reflector element of my 2 element 40 out of exact
> horizontal. I would guess that the reflector is about 20 degrees off of
> horizontal. I have noticed a degradation in my yagi performance. Can anyone
> tell me from experience or modeling what effect 20 degrees of rotation of
> the reflector in a 2 element yagi, or any element for that matter has on
> forward gain and beam performance.
>
> Any help/information would be greatly appreciated.
>
> Gary W5FI
>
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