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Vertical help WTD

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JEFF UK

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Nov 20, 2004, 3:30:18 PM11/20/04

Hi again.
Just wondering....
i have a coax fed long wire running along my garden fence at the moment for
swl ...
i have a old spare Antron 99 vertical CB antenna here..
how can i attach this to the end of my long wire to give me some vertical
reception ?
Or should i put it In Line with the long wire ?
I was wondering if the braided side of the coax on the Antron should go to a
earth stake ?
Any suggestions ?
Just wondering,
Regards
Jeff

Volker Tonn

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Nov 20, 2004, 6:03:45 PM11/20/04

JEFF UK schrieb:

Is this the 1/2 lambda or the 5/8lambda version?
In the 1st case you can add an antenna (versa-) tuner and use this
antenna seperately for the 60 to 10 meter bands. In 2nd case in addition
you should have to jumper the coil. A vertical antenna has some gain
in receiving DX of more than 5000 miles over a horizontal antenna when
matched(!) properly.
Using this antenna for lower bands is not recomended as ist is then
shorter than a 10th of the wavelegth wich will decrease gain drastically.
Using this antenna in conjunction with a longwire doesn't make too much
sense. Allmost all SW-transmission is polarizised horizontally. But
reflection on the ionosphere mixes it up all the way toyour antenna. So
in result it is somewhat like a lottery having the receiving antenna
polarized in best angle :-) So an inverted-V of 2 legs with 60- 100 ft
in 90 degress V-angle with an antenna tuner is a very good
omnidirectional broadband performer.

RHF

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Nov 22, 2004, 3:41:43 AM11/22/04

= = = "JEFF UK" <Birdn...@btopenworld.com> wrote in message
= = = news:<cno9gq$s39$1...@titan.btinternet.com>...

JEFF UK,

Any 1/4WL, 1/2WL 5/8WL Vertical Ground Plane CB Antenna can be
used as a SWL Antenna. Try this CB Antenna as a direct-hook-up
via Coax Cable to you receiver - just to see what you can receive.
NOTE - A properly installed CB Antenna that is Grounded;
Fed with a Coax Cable; and 'remote'(far) from the House/Building;
can be an effective Vertical SWL Antenna.
[When Nothing else is available.]

A Better Idea May Be - The Inverted "L" Antenna:
If you have the space an room for the Antron 99 Vertical CB Antenna.
You have the space and room to install a piece of Top-Rail
(Top-Rail = a single 21 Feet of 1 3/8" Steel Pipe) as an antenna
support. Mount an Eye-Bold or a Pully at the Top of the Top-Rail
for the 40-50 feet of 1/8"-3/16" Nylon Rigging Rope that is used
to secure your Wire Antenna Element.

About Three Feet from your House; run/route a Wire Antenna
Element from ground level up alone-the-side (about 1'-3' away)
of the House up to the Roof; and out to the top of the Top-Rail.
You now have an Inverted "L" Antenna.

Install a Ground Rod at the Point on the ground where you started
the Antenna Wire Element.

Build/Buy a Matching Transformer (UnUn-Balun) and mount it on
the Top of the Ground Rod.

Run/route a Coax Cable from the Ground Rod to your Radios/Receivers.

Connect the Wire Antenna Element; the Coax Cable; and the Ground
Rod/Wire all to the Matching Transformer.

If Possible - "Do It" in Reverse.

Run/Route a Coax Cable from your Radios/Receivers out to the
piece of Top-Rail. (Bury the Coax Cable if possible.)

About Three Feet from the Top-Rail run/route a Wire Antenna
Element from ground level straight-up to the Top of the Top-Rail;
and then Out-Across-to the Top of your Roof. You now have an
Inverted "L" Antenna.

Install a Ground Rod at the Point on the ground where you started
the Antenna Wire Element.

Build/Buy a Matching Transformer (UnUn-Balun) and mount it on
the Top of the Ground Rod.

Connect the Wire Antenna Element; the Coax Cable; and the Ground
Rod/Wire all to the Matching Transformer.

If you want a 'Set of Numbers' to Build their SWL Inverted "L"
Antenna here are a few 'Sets of Numbers' to consider for your
available space:
- 10 Ft High Vertical 'Leg' with a 20-30 Ft Horizontal Arm
having a Total Lenght of 30-40 Feet. Also: 20x40-60 & 30x60-90
- 15 Ft High Vertical 'Leg' with a 30-45 Ft Horizontal Arm
having a Total Lenght of 45-60 Feet.
- 25 Ft High Vertical 'Leg' with a 50-75 Ft Horizontal Arm
having a Total Lenght of 75-100 Feet.
- 35 Ft High Vertical 'Leg' with a 70-105 Ft Horizontal Arm
having a Total Lenght of 105-140 Feet.

IF - You have Trees to work with as supports for your Antenna
Wire Element. Consider using Insulated Stranded Wire for the
Antenna Element and run/routing it up into and through the
Trees to make your Inverted "L" Antenna.

iane ~ RHF
.
Some Say: On A Clear Day You Can See Forever.
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/502
I BELIEVE: On A Clear Night...
You Can Hear Forever and Beyond, THE BEYOND !
.
.

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