Perfect Antenna
 

Hi All,

I am looking for my "perfect antenna". It should work on 75m-6m, with NVIS on
75m & 40m and good DX for 20m and above. Above all it must fit in my backyard
which is 34 by 50 feet. The use of a tuner and/or balanced line is fine.

By perfect, I mean an antenna that gets the RF out (reasonable efficiency as a
percentage).

At first, I considered a random loop of 34 ft by 50 ft, at about 20 to 30 feet
high, with window line, but am having second thoughts.

Any ideas or suggestions?

Randy KA4NMA

try putting up the loop anyway...and opening it opposit of the feedpoint for
use on 80 meters. I will probably work just fine.
"Theplanters95" wrote in message
...
Hi All,

I am looking for my "perfect antenna". It should work on 75m-6m, with
NVIS on
75m & 40m and good DX for 20m and above. Above all it must fit in my
backyard
which is 34 by 50 feet. The use of a tuner and/or balanced line is fine.

By perfect, I mean an antenna that gets the RF out (reasonable efficiency
as a
percentage).

At first, I considered a random loop of 34 ft by 50 ft, at about 20 to 30
feet
high, with window line, but am having second thoughts.

Any ideas or suggestions?

Randy KA4NMA

On 03 Mar 2004 06:35:41 GMT, ospam
(Theplanters95) wrote:

Hi All,

I am looking for my "perfect antenna". It should work on 75m-6m, with NVIS on
75m & 40m and good DX for 20m and above. Above all it must fit in my backyard
which is 34 by 50 feet. The use of a tuner and/or balanced line is fine.

By perfect, I mean an antenna that gets the RF out (reasonable efficiency as a
percentage).

At first, I considered a random loop of 34 ft by 50 ft, at about 20 to 30 feet
high, with window line, but am having second thoughts.

Any ideas or suggestions?

Randy KA4NMA


Randy ,

I Think the loop would work well for you under the perameters you
mentioned.. it should be good NVIS on 80 & 40 and begin to show low
angle radiation above those bands. you may have to do so work to get
it load well for you on 80m though it's a bit short there..

I've use a 520' Horizontal loop here for number of years with good
results.. it averages about 30' above ground.

73 Dave

I had a loop that was about 200 feet, and it was triangular.

The only reason I took it down was that the way my trees had grown it was
getting tangled on a regular basis.

Fed it with 300 ohm tv line. Several different tuners WITHOUT a balun
worked fine on the loop. I also used a Balanced (Johnson matchbox) tuner on
the loop with good results.

John
KA9CAR



"KC1DI" wrote in message
...
On 03 Mar 2004 06:35:41 GMT, ospam
(Theplanters95) wrote:

Hi All,

I am looking for my "perfect antenna". It should work on 75m-6m, with
NVIS on
75m & 40m and good DX for 20m and above. Above all it must fit in my
backyard
which is 34 by 50 feet. The use of a tuner and/or balanced line is fine.

By perfect, I mean an antenna that gets the RF out (reasonable efficiency
as a
percentage).

At first, I considered a random loop of 34 ft by 50 ft, at about 20 to 30
feet
high, with window line, but am having second thoughts.

Any ideas or suggestions?

Randy KA4NMA


Randy ,

I Think the loop would work well for you under the perameters you
mentioned.. it should be good NVIS on 80 & 40 and begin to show low
angle radiation above those bands. you may have to do so work to get
it load well for you on 80m though it's a bit short there..

I've use a 520' Horizontal loop here for number of years with good
results.. it averages about 30' above ground.

73 Dave

Nomen Nescio wrote:
In article
ospam (Theplanters95) wrote:
I'd love to see this thread expand to answers. Many of us have the same
wants, maybe not all the bands, but a least 80-10 in the confines given
above. Many solve with a vertical but I for one, would like something
better.

This has been covered before but bears repeating. Consider a 40m
full-wave square loop of about 138 feet, about 34 ft. per side.
If an insulator is installed halfway around the loop from the
feedpoint, the antenna becomes 1/2WL on 80m. Figure out an easy
way to short the insulator out for 40m-10m operation and open the
circuit at the insulator for 80m operation. Three possibilities
come to mind.

Locate the insulator on a pulley on one of the support poles and
lower that point on the antenna for physical access. Shouldn't
take more than 5 minutes to accomplish the short/open function.

Install a 1/4WL shorted stub for 80m operation. That will give an
open circuit on 80m and a short circuit on any multiple of 3.8 MHz,
for instance.

I once rigged up a Rube Goldberg high voltage switch out of copper
tubing supported by PVC pipe. One end of the antenna was attached
to a piece of 1/2 inch copper tubing. The other end was attached
to a piece of 1/4 inch copper tubing. By tugging on one of two
strings, I could move the 1/4" tubing in or out of the 1/2" tubing.
More elegant than strings would be a small screwdriver motor powered
by +/- DC from the shack end of the transmission line.
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

Yes Cec, to use a vertical 1/4-wave line is a neat way of shorting and
opening a horizontal wire at a single frequency from ground level.

I once used a sealed reed relay to do a similar job. One of the horizontal
antenna wires was in fact twin 20-gauge speaker cable to operate the relay
coil. The shack end of the twin wire required a bifilar choke wound on a
ferrite rod to separate RF from the DC relay supply.
---
Reg, G4FGQ