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Old August 24th 07, 10:03 AM posted to
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First recorded activity by RadioBanter: Jun 2006
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Default Part II : Beyond the Simple One-Wire Outdoor Shortwave Antenna

More Answers To Follow . . .

Part II : Beyond the Simple One-Wire Outdoor Shortwave Antenna

OK so you have your Eton E1 Radio and you want more out of it.

Clearly besides a new Radio the only major way of doing this
is a better Shortwave Antenna for the Radio.

Assume you live in an Urban Area and AM/MW Radio Stations
become a problem when you start using an External "Longwire"
Antenna with your Radio.

Assume that you have the Space for an External Antenna and
that there are No Restrictions on Outside Antennas.

Now lets start with your eton E1 Radio : It uses a PAL Jack
for the external Shortwave Antenna connection.

So first of all you need a PAL Plug to mate-up with the
PAL Jack on the Radio.

-Note- The PAL Connections are the EU {World Wide}
equilvalent of the USA's "F" Connector. and most of
them work well with TV type 75 Ohm Coax Cable.
-OR- You could use a PAL to "F" Adaptor.

So why not use TV type 75 Ohm Coax Cable as your Shortwave
Antennas feed-in-line !

Converting from the Coax Cable to the Wire Antenna Element(s).
To 'match' the Coax Cable to the Wire Antenna you will need
a Matching Transformer. The simplist an most common to find
is the 300 Ohm to 75 Ohm TV type Matching Transformer.
-Note- The TV type Matching Transformer greatly attenuates
the RF Signals below 5 MHz so to some extent it is an AM/MW
Band Rejection Filter.
The Two 300 Ohm Wire Leads of the Matching Transformer
give you a few Shortwave Antenna Options :
* Dipole or Inverted "V' or Multi-Dipole Antenna
* Windom Antenna
* Horizontal Wire Antenna {Longwire / Random Wire}
* Inverted "L" Antenna
The Dipole and the Windom both use each of the Two 300 Ohm
Wire Leads like a Balun. And you can either Cut them to a
Shortwave Band Size -or- Cut them to fill the Available Space
you have to work in Safely.

Examples of Cut-To-Size Dipole Antenna Sizes :
60m = 95.4 Feet Tip-to-Tip or = 47.7 Feet per Arm
49m = 77.0 Feet Tip-to-Tip or = 38.5 Feet per Arm
41m = 63.7 Feet Tip-to-Tip or = 31.8 Feet per Arm
31m = 49.0 Feet Tip-to-Tip or = 24.5 Feet per Arm
25m = 39.3 Feet Tip-to-Tip or = 19.7 Feet per Arm
22m = 34.1 Feet Tip-to-Tip or = 17.7 Feet per Arm

Examples of Cut-To-Size Windom Antenna Sizes :
60m & 41m = Long Arm 47.7 Feet and 31.8 Feet Short Arm
49m & 31m = Long Arm 38.5 Feet and 24.5 Feet Short Arm
31m & 22m = Long Arm 24.5 Feet and 17.7 Feet Short Arm

-Note- The Dipole and Windom Antennas are 'balanced'
Antennas and a Ground may not be needed to make them
function well.

The Horizontal Wire and Inverted "L" Antennas are single
Wire Antennas and you will use one of the 300 Ohm Lead
to connect to the Wire Antenna Element and . . .
What Do I Do with the 'other' Lead ? ? ?
Connect a short 3-4 Inch Bare Wire to this other Lead
and use a Hose Clamp to Secure it to the outside of the
"F" Connector attached to the 75 Ohm Connector of the
Matching Transformer - you now have a Magnetic Longwire
Balun (MLB).

The Horizontal Wire Antenna can be any Random Length Wire
that you can Safely Rig within your Property Limits.

The Inverted "L" Antenna can be any Random Length Wire
that you can Safely Rig within your Property Limits.
-OR- Inverted "L" Antenna can be Cut-to-Size

Examples of Cut-To-Size Inverted "L" Antenna Sizes :
31m & 60m = Vert-Leg 24.5 Feet and Horiz-Arm 47.7 Feet
25m & 49m = Vert-leg 19.7 Feet and Horiz-Arm 38.5 Feet
19m & 41m = Vert-Leg 15.1 Feet and Horiz-Arm 31.8 Feet
{ Relative Aspect Radio 1V : 2H }

-Note- The Horizontal Wire and Inverted'L" Antennas are
'un-balanced' Antennas and a Ground will be needed to
make them function properly.

For the Coax Cable feed-in-line i recommend RG6 Quad
Shield Coax Cable. As musch as you need to get from
you Eton E1 Radio to your Matching Transformer and
Wire Antenna Elements.

All of these above Wire Antennas should have lower Noise
and better Signal Levels then a simple plain wire Antenna;
and provide for a more enjoyable Shortwave Listening (SWL)

hope this helps - iane ~ RHF {pomkia}
Shortwave Listener (SWL) Antennas Group =
GoTo =
The SWL Antenna Discussion Group =
Shortwave Listener (SWL) Antenna HELP =
Shortwave Listener (SWL) Antenna NEWS =
Shortwave Listener (SWL) Antenna INFO =
* * * All Are Welcome : Including ELMERS and 'Want-to-be-Elmers'
plus plain old "Mister-Know-It-Alls"; and even those Newbees with
"I Know This Is A Really Dumb Question - But _ _ _ _ _ _ _ _ "
The Shortwave Listener's Blessing :
May You Never Tire of Listening to the Radio and Always
have Strong Signals and Noise Free Reception ~ RHF {ibid}
Tous Sont Bienvenus ! - - - Groupe par Radio
d'auditeur d'onde courte pour des Antennes de SWL
Alle Sind Willkommen ! - - - Shortwave Radiozuhörer
Gruppe für SWL Antennen
Tutti Sono Benvenuti ! - - - Gruppo Radiofonico
dell'ascoltatore di onda corta per le Antenne di SWL
Todos São Bem-vindos ! - - - Grupo de Rádio
do ouvinte do Shortwave para Antenas de SWL
¡Todos Son Agradables! - - - Grupo de Radio del oyente
de la onda corta para las Antenas de SWL
= = = = Plain Old American-English Translation = = = =
All are Welcome - - - To Join the Shortwave Listeners
(SWL) Antenna Group on YAHOO !
/ \