For One and All,
Question is 'it' a Longwire {Random Wire} Antenna -or- Inverted "L"
Antenna ?
http://groups.yahoo.com/group/Shortw...a/message/6300
AMATEUR [HAM] - INVERTED "L" ANTENNA :
The traditional Amateur (Ham) Inverted "L" Antennas used
as both a Transmitting and Receiving Antenna usually were
Symmetric Dimensioned Vertical and Horizontal Antennas.
Vertical - - - Horizontal - - - - Total
"Up Leg" - - - "Out Arm" - - Length
Half - - - - - - - Half - - - - - - - Full
1/8 WL = = = 1/8 WL = = = 1/4 WL for XX Meter Band
1/4 WL = = = 1/4 WL = = = 1/2 WL for XX Meter Band
1/2 WL = = = 1/2 WL = = = One WL for XX Meter Band
SHORTWAVE LISTENER {SWL} - INVERTED "L" ANTENNA :
However, the Shortwave Listener (SWL) Inverted "L" Antenna
is usually an Asymmetrical Dimensioned Antenna with a 'shorter'
Vertical "Up" Leg and a 'longer' Horizontal "Out" Arm. For
the Shortwave Listener (SWL) the Inverted "L" Antenna is
generally built as an "Available Space" Antenna for Receive
'Only'. It goes as HIGH as "I Got Something to Hang it From"
and as Long as "I Got Something to Hang It Between".
Most of the Time the "Up Part" is 10-15-20-25 Feet High.
Most of the Time the "Out Part" is 20-30-40-50 Feet Long.
Often the Horizontal Out-Arm is Two (2X) to Three Times (3X)
the Length of the Vertical Up Leg.
The Shortwave Listener (SWL) Inverted "L" Antenna is
usually described as
Vertical - - - Horizontal - - Total
"Up Leg" - - - "Out Arm" - - Length
( 1/3 ) - - - - ( 2/3 )- - - - Full
10 Feet + + + + 20 Feet = = = 30 Foot Long Random Wire
15 Feet + + + + 30 Feet = = = 45 Foot Long Random Wire
20 Feet + + + + 40 Feet = = = 60 Foot Long Random Wire
25 Feet + + + + 50 Feet = = = 75 Foot Long Random Wire
30 Feet + + + + 60 Feet = = = 90 Foot Long Random Wire
Vertical - - - Horizontal - - Total
"Up Leg" - - - "Out Arm" - - Length
( 1/4 ) - - - - ( 3/4 )- - - Full
10 Feet + + + + 30 Feet = = = 40 Foot Long Random Wire
15 Feet + + + + 45 Feet = = = 60 Foot Long Random Wire
20 Feet + + + + 60 Feet = = = 80 Foot Long Random Wire
25 Feet + + + + 75 Feet = = = 100 Foot Long Random Wire
30 Feet + + + + 90 Feet = = = 120 Foot Long Random Wire
The majority of these Shortwave Listener (SWL) Inverted "L"
Antennas "Fit" into the Sizing Range of 12 to 24 Feet High
by 24 to 72 Feet Long which is about 36 to 96 Feet in Total.
KC7NOD refers to the Shortwave Listener's (SWL) Inverted
"L" Antenna simply as an "Improved Random Wire Antenna"
http://www.kc7nod.20m.com/improved_rw.htm
Read his description he says it all very well and briefly.
http://groups.yahoo.com/group/Shortw...na/message/466
- - - - - TO QUOTE A PRIOR MESSAGE BY ME - - - - -
* * * EXTRACTED from Newsgroups: Rec.Radio.Shortwave
= = = From: (RHF)
= = = Date: 11 May 2004 01:22:51 -0700
= = = Local: Tues, May 11 2004 12:22 am
= = = Subject: ABOUT - Inverted "L" antennas
This is why a Receive ONLY Shortwave Listeners (SWL) Antenna
one that is Omni-Directional generally works better then one
that is intended to be directional.
* The SWL Version of the Inverted "L" Antenna works well as
an Omni-Directional Antenna. The SWL Inverted "L" Antenna
usually has a Vertical 'Leg' that is 1/3 to 1/2 the Length of
the Length of Horizontal 'Arm'. Plus the SWL Inverted "L"
Antenna usually is lower to the Ground. This closeness to the
Surface of the Ground results in the SWL Inverted "L" Antenna
being a form of "Near Vertical Incident SkyWave" {NVIS} Antenna.
NVIS=
http://www.qsl.net/k5eph/nvis.htm
* These SWL Versions of the Inverted "L" Antennas can be any
size because they are in-fact simply Random Wire Antennas that
are designed to fit the available space.
http://groups.yahoo.com/group/Shortw...nna/message/54
* The Inverted "L" Antenna 'Shape' lends itself to the Design
Concepts of a "Low Noise Antenna" that has been popularized
by John Doty; consisting of: Antenna Element; Matching Transformer;
Grounding Point; Coax Cable Feed-in-Line; Radio/Receiver.
DOTY=
http://www.anarc.org/naswa/badx/ante...e_antenna.html
http://groups.yahoo.com/group/Shortw...enna/message/2
http://groups.yahoo.com/group/Shortw...na/message/374
- Two Reasons to use a Balun (Matching Transformer)
with a Receive Only Antenna.
DOTY=
http://www.anarc.org/naswa/badx/ante..._longwire.html
http://groups.yahoo.com/group/Shortw...na/message/150
- Magnetic Longwire Balun (MLB) - Build Your Own "DIY"
http://groups.yahoo.com/group/Shortw...na/message/177
http://groups.yahoo.com/group/Shortw...na/message/466
http://groups.yahoo.com/group/Shortw...na/message/467
- Balun Reading List ( Long )
http://groups.yahoo.com/group/Shortw...na/message/337
- The "Grounding-Point" = Ground Rods and Ground Wires ETC.
DOTY=
http://www.anarc.org/naswa/badx/antennas/grounding.html
http://groups.yahoo.com/group/Shortw...na/message/425
http://www.hard-core-dx.com/nordicdx/antenna/ground/
http://groups.yahoo.com/group/Shortw...na/message/470
http://groups.yahoo.com/group/Shortw...na/message/539
For those who 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:
- 10Ft High Vertical 'Leg' with a 20-30Ft Horizontal Arm
having a Total Length of 30-40 Feet. Also: 20x40-60 & 30x60-90
- 15Ft High Vertical 'Leg' with a 30-45Ft Horizontal Arm
having a Total Length of 45-60 Feet.
- 25Ft High Vertical 'Leg' with a 50-75Ft Horizontal Arm
having a Total Length of 75-100 Feet.
- 35Ft High Vertical 'Leg' with a 70-105Ft Horizontal Arm
having a Total Length of 105-140 Feet.
NOTE: The Amateur/HAM Inverted "L" Antenna is usually made-up
of Two Equal Sections One Vertical 'Leg' and One Horizontal 'Arm'.
These Two Equal Section can be:
* 1/8th Wavelength = Quarter Wavelength Total
* 1/4th Wavelength = Half Wavelength Total
* 1/2th Wavelength = One Wavelength Total
Because of the 'equal' proportionality, the Amateur/HAM
Inverted "L" Antenna is most often Higher above the Ground
then the SWL Version.
Dr. Ace's [WH2T] Inverted L Antenna Info
ACR=
http://www.bloomington.in.us/~wh2t/invertedl.html
http://groups.yahoo.com/group/Shortw...na/message/309
iane ~ RHF
- - - - - Un-Quote - - - - -
MORE MESSAGES TO READ :
The 'Best Shape' (Configuration) Antenna that lends itself to the
Low Noise Antenna Design is the Inverted "L" Antenna.
http://groups.yahoo.com/group/SWL-AM...nna/message/10
Understanding the Random Wire Antenna . . .
and Building a Better One !
http://groups.yahoo.com/group/Shortw...na/message/200
Inverted "L' Antenna Reading List
http://groups.yahoo.com/group/Shortw...na/message/374
"LOW NOISE SWL ANTENNA" - by Mark Connelly [WA1ION]
http://groups.yahoo.com/group/Shortw...na/message/119
"Another Look at Noise-Reducing Antenna Systems"
Inverted "L" Antenna as an 'available space' SWL Antenna
http://groups.yahoo.com/group/Shortw...nna/message/54
"LOW NOISE SWL ANTENNA" - popularized by John Doty.
http://groups.yahoo.com/group/Shortw...enna/message/2
MORE LINKS TO READ :
RRS =
http://tinyurl.com/8wj86
RRS =
http://tinyurl.com/aw7ox
iane ~ RHF
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Tous Sont Bienvenus ! - - - Groupe par Radio
d'auditeur d'onde courte pour des Antennes de SWL
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
Alle Sind Willkommen ! - - - Shortwave Radiozuhörer
Gruppe für SWL Antennen
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
Tutti Sono Benvenuti ! - - - Gruppo Radiofonico
dell'ascoltatore di onda corta per le Antenne di SWL
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
Todos São Bem-vindos ! - - - Grupo de Rádio
do ouvinte do Shortwave para Antenas de SWL
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
Все *адушны ! - - - Группа оператора
на приеме коротковолнового диапазона
Radio для Aнтенн SWL
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
¡Todos Son Agradables! - - - Grupo de Radio del oyente
de la onda corta para las Antenas de SWL
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
= = = = = Translation = = = = =
All are Welcome - - - To Join the Shortwave Listeners
(SWL) Antenna Group on YAHOO !
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
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