[TowerTalk] OptiBeam OB2-40M

[Lux, Jim]

On 5/22/21 8:42 AM, k7lxc--- via TowerTalk wrote:
>>    Sorry, but I don't believe any of that.? It sounds purely anecdotal.     Anecdotal?!? Ha - most of the stuff you get here is anecdotal along with lots of different opinions.     Here's more anecdotal. I had an original KLM 4L 40M beam that always seemed to break during the winter and require a major effort to repair every summer. I bought a CC 402CD to replace it and set it to the Secret LXC dimensions. The KLM never played like I thought a big 3L yagi should have. (I didn't count the dual driven elements.) Anecdotally I was much happier with the CC performance plus it didn't have to be repaired every year!      My budget dream 40M array? A 2 stack of CC antennas. You don't need big bucks or rotators to turn the danged things plus you have a choice of arrival/takeoff angles and 2 different potential headings at the same time. IMO there's no downside and you save LOTS of money. I'm just saying.  Cheers,Steve    K7LXC

This is an interesting observation - Yagis are just a phased array, 
using mutual coupling to excite the other elements. And a single flat 
antenna has an elevation pattern that is determined almost entirely by 
the height above ground.

If you have a constraint on "number of elements" are you better off with 
a longer array with more elements or with two stacked arrays with fixed 
phasing?  In the VHF world, people turn to arrays when the length of a 
single antenna gets unwieldy  ( http://www.w5un.net/EME%20Array.JPG) - 
and there are some performance advantages too.

If you remove the constraint of fixed phasing (which is what the steppir 
does, and so does the "stackmatch"), then which is better?

if you have an adjustable LC network at the feed of a yagi, or a fully 
driven array, what (real) advantage does that confer?


In the HF broadcast world, there's definitely people building arrays 
that are steerable in both azimuth and elevation - but I'm not sure 
their "figure of merit" is the same as a ham.