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.
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