[TowerTalk] Optimum Stacking Distance

Tom Rauch W8JI@contesting.com
Fri, 27 Jul 2001 22:27:58 -0400


Hi Yuri,

> Hmmm,
> and narrower antenna pattern has nothing to do with (longer) boom length?

No. They are not directly related. What if I stacked two dish antennas? What is the boom length of a dish?

For example, your own super 10dB-over-a- 5-element-yagi-super-
razor beam antenna would require a much wider stacking distance 
than the lower gain yagi, because the pattern is "razor sharp" 
compared to a yagi of the same boom length.

It always works by pattern width, it only works by boom length by 
odd coincidence or blind luck.   

> Some contradiction going on here (again). Isn't it a bit farfetched to
> compare stacked dipoles (zero boom) to typical multielement antenna
> (bigger boom, bigger gain/narrower pattern, etc.) situations?

The normal way to check the validity of a statement is to take it to 
extremes and see if the rule works. Even if someone is unfamiliar 
with that normal procedure to prove a statement, I also compared a 
short-boom yagi.

 > With stacked Razors (1.2 wave booms) I used about 1.2 wave spacing, based
> on experiences of others, mainly VHF crowd (no software back then), worked
> like the fine tuned Stradivarius.

I'm sure it did. No one can make antennas work like you can.
73, Tom W8JI
W8JI@contesting.com 


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