It's not totally clear to me how you get 500 feet out of that sketch
(I'm probably misunderstanding your description), but I don't think that
configuration would work well at all, at least not as a Beverage. A
Beverage is a traveling wave antenna and current is induced in the wire
from RF arriving along the length of the wire. Almost none of your wire
is in the proper direction for that. Also, the folded back segments are
spaced closely enough, and the segments are a small enough percentage of
a wavelength (meaning that the currents in adjacent wires are
approximately in phase but going opposite directions), that I suspect
whatever fields that actually get induced would mostly cancel each other.
Just my opinion ...
Dave AB7E
On 10/30/2017 5:22 PM, Rick Braddy wrote:
Hi,
I am investigating a potential new design for a Beverage-like antenna that
is much shorter than the traditional long-wire Beverage, that many (most?)
of us do not have enough space to deploy. I originally posted this concept
on the Flex Radio forum here
<https://community.flexradio.com/flexradio/topics/meandering-line-square-wave-beverage-antenna-for-160-meters>,
which resulted in many excellent suggestions, including one to post to this
reflector to see if there's anyone with NEC modeling skills who can assist
me in getting this model across the finish line (my 4nec2 skills are still
developing).
https://community.flexradio.com/flexradio/topics/meandering-line-square-wave-beverage-antenna-for-160-meters
It's entirely possible that I may be barking up the wrong tree, but if this
concept antenna does work and perform reasonably well, it would provide
many of us an option for 160 and 80 meter DX'ing. The basic idea is to
fold the lengthy Beverage antenna up into a series of "meandering lines"
that (to me) look like a square wave. These antennas are very popular and
effective on VHF and IoT devices at 2.5 Ghz, and have been successfully
deployed in radar and military HF applications, although there's relatively
little research published on them. This style of design would result in
reducing the space required for the antenna by a factor of 10 or more (from
580 feet down to perhaps 50).
In particular, the last post at the link above includes the current NEC
model file, some charts showing the results thus far (which are
inconclusive at best), and a link to the "C" program I'm using to generate
the NEC model. I could use some consulting help to refine my NEC model to
properly simulate the terminating resistor and perhaps other tweaks to get
the model working well.
Thanks in advance for pointing me in the right direction and any assistance.
Rick
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