[ARC5] Antenna for small yard

[Jim Wiley]

Keep in mind there is nothing anywhere that says an antenna must be 
"naturally resonant" or any specific length whatever to be a good 
radiator, nor  is it necessary for an antenna to have a low SWR at 50 
ohms to radiate well.  There IS a requirement that the antenna (and 
feedline)  be adjusted in such a way that a "conjugate match" exists 
between the transmitter and antenna. The antenna should probably be at 
least 1/4 wavelength at the lowest frequency being used,  but don't be 
afraid to try shorter, longer or even random length wires.

If the feedline is of low loss construction (think open wire feeders), 
and the antenna coupling unit (antenna tuner) is properly adjusted, any 
reflected power will simply bounce up and down the feedline until it is 
eventually radiated.

Antenna theory is complex at best.  Consider the next two points:

(1) One of the best books on the subject is "Reflections" (or 
"Reflections II")   by Walter Maxwell.  Get a copy and read it, I 
guarantee it will open your eyes.   You should probably have your own 
copy.   New or used are equally good.

(2) Along with a copy of "Reflections",  you should have a recent copy 
of the ARRL antenna book.  A brand new copy is not required. Anything 
within the last 10 years will do.

Do NOT let some inexperienced or ignorant person try to convince you 
that a SWR above 1:1 will deduct from your signal, this is simply not 
true. I have successfully used HF antennas at SWRs exceeding 10:1 - the 
trick is matching the transmitter to the  load.  If you can do that, the 
antenna WILL radiate.

Also, keep in mind that ANY antenna is better than  no antenna! 
Experiment and try different approaches.  Someone suggested folding 
(bending) the radiating element so it fits into the available space.  By 
all means try that approach.

The suggestion by Glen Zook (on this reflector) to use a "L" shaped 
antenna 9 by 24 feet is a good one.   Be sure to have a good "ground" 
connection in the event you are using a single wire antenna.  Having the 
best ground connection you can manage is critical to good performance 
for this configuration.

Finally,  these suggestions pertain mainly to HF antennas.  Antennas for 
VHF and UHF have different considerations.

- Jim, KL7CC





On 10/21/2016 5:01 PM, J Mcvey via ARC5 wrote:
> Yeah, where there's a will there's a way! Not to mention that a 24 ft 
> square has a perimeter of 96 feet and a 33.9 foot diagonal.!.
>
> Maybe 18ft is an optimal short length for 40 meters?  I was able to 
> load up to 23 ft of wire on 40. I was testing to find out how long was 
> too long.
> My thinking was once you are below 1/4 wavelenth, it's not really a 
> resonant antenna anymore, or ar least not a good one.
> The E amplitide increases per unit length, so wouldn't longer be better?
> Next up: propagation tests?
>
>
> On Friday, October 21, 2016 7:50 PM, Glen Zook via ARC5 
> <arc5 at mailman.qth.net> wrote:
>
>
> Run 9-feet vertically and 24-feet horizontally.  Will work very well!
>
>
> Glen, K9STH
>
> Website: http://k9sth.net
>
>
> ------------------------------------------------------------------------
> *From:* AKLDGUY . <neilb0627 at gmail.com>
> *To:* Mike Everette <radiocompass at yahoo.com>; ARC-5 List 
> <arc5 at mailman.qth.net>
> *Sent:* Friday, October 21, 2016 6:46 PM
> *Subject:* Re: [ARC5] Antenna for small yard
>
> Please tell me how I'm supposed to fit a 33 foot antenna into a 24 
> foot yard.
>
>
>
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