[TowerTalk] Meandering line "square wave" antenna design for shorter 160m Beverage?

[David Gilbert]

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
>