Part # 1 - The Simplest Shortwave Listener (SWL) Antennas That I Know Of . . .
RHF
Part # 1 - The Simplest Shortwave Listener (SWL) Antennas
That I Know Of . . .
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/9894
One of the simplest Shortwave Listener (SWL) Antennas
that I know of is a Doublet {Dipole} Antenna made from
- - - Guess What . . . Speaker Wire !
This simple a Doublet {Dipole} Antenna can be Rigged Out-Side
-or- In-the-Attic if needed.
NOTE - Larger Size AWG Stranded Speaker Wire is Preferred.
First - Buy a 50 Foot Roll of Speaker Wire.
Roll-it-out and fold-it-over in the center forming two pieces
25 Feet long and tie a Loop Knot at this Center Point.
* The 'common' Overhand Loop Knot
http://www.outdoorcanada.ca/fish/loop_knot.shtml
* Figure-of-Eight Loop Knot
http://en.wikipedia.org/wiki/Figure-of-eight_loop
* Surgeon's Loop Knot
http://en.wikipedia.org/wiki/Surgeon%27s_loop
" KNOTS " => http://en.wikipedia.org/wiki/Knot
Antenna-End of the Speaker Wire :
Split the Two Wires apart {separate them} along one
piece of the Speaker Wire and again tie an Overhand
Loop Knot at both of the Split-Ends. Tie a Nylon-Poly
Rope for Rigging to the each of the Overhand Loop Knots
{all three} Center and both Ends. The Two Arms that
are formed are about 25 Feet long and the Tip-to-Tip
Length of the Wire Antenna Element is about 50 Feet.
A Doublet {Dipole} Antenna of this Length is 'cut'
for the 31 Meter Shortwave Band.
-IF- 50 Feet is a Bit-to-Long one Arm can be shorted by
Rolling-Up the Antenna Wire Element into a Four-Inch
Circle of about Eight Turns {Wraps} and securing the
Coil; this will shorten that Arm down to 17 Feet for
a Tip-to-Tip Length of 42 Feet.
- - - You now have transformed your Dipole Antenna
into an improved Windom Antenna {Off-Center-Fed-Dipole}.
Radio-End of the Speaker Wire {Feed-in-Line} :
At the End where the Two Wires are still together
separate them about Three Inches and Strip the
Insulation away from first {last} Inch and [Optional]
Tin {Solder} about a Half-Inch of both of the Wires.
Note - Some will take the time to Twist the Two Wires
along their full feed-in-line length to improve their
function as a feed-in-line -vice- antenna element.
RIG -The Antenna-End of the Speaker Wire a Flat
about 12-15 Feet above the surface of the ground.
ATTACH - The Radio-End of the Speaker Wire to the
Receiver's Twin Antenna Terminals -or- the Radio's
1/8" Mono-Jack using an 1/8" Mono-Plug to make the
connection into the Radio.
SUMMARY - A simple basic Antenna using One Piece
of Speaker Wire that is easy to find anywhere and
relatively low cost. Plus a Spool of common Mason
Line for Rigging the Wire Antenna Element.
Easy - To Make with one common Tool a Knife.
Repeatable - Hard Not To Build, Rig and Connect Right.
Reasonable Performance - Based on the Materials,
Time and Money that it Cost to Make and Install.
CAUTION - Be Sure To Ground Your Radio Shack's
Equipment when using any External {Out-Side} Antenna.
Next - Part # 2 - The Same Idea Taken In-Side {In-Doors}
and Guess What . . . It Is Ready Made !
Keeping It Simple And Practical - iane ~ RHF
.
Shortwave Listener Antennas => http://tinyurl.com/ogvcf
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SWL Antenna Group => http://tinyurl.com/ogvcf
.
The Shortwave Listener's Blessing :
SWL BLESSING => http://tinyurl.com/s2bjm
May You Never Tire of Listening to the Radio and Always
have Strong Signals and Noise Free Reception ~ RHF {ibid}
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/9233
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RHF
Next - Part # 2 of "The Simplest Shortwave Listener (SWL) Antennas
That I Know Of..." - The Same Idea Taken In-Side {In-Doors} and
Guess What . . . It Is Ready Made !
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/9929
One again this simple Antenna is a form of a Doublet {Dipole} Antenna
but it is much smaller and can be used as an In-Door Antenna for
Shortwave Listening.
IT IS THE FM FOLDED DIPOLE ANTENNA - ? WHAT ?
Hey - That is too short and small for a Shortwave Antenna !
Well Yeah and so is the Whip Antenna that is built into
every 'portable' AM / FM Shortwave Radio. When putting
an Antenna {Any Antenna} In-the-Room is all you can do;
and making an Antenna yourself is not an option; and
you Antenna Budget is under $5. You are limited in just
'what' you can do for an Antenna and your Antenna choices.
WHAT - Is very common and available and cheap that is
Ready-Made and can be used as a Antenna for Shortwave
Listening (SWL) with :
* Most 'portable' AM / FM Shortwave Radios with an 1/8"
Mono-Jack External Antenna Input -How- Remove the Antenna
Terminals and connect the Antenna Wires to an 1/8" Mono
Plug and plug that into the Radio.
* Shortwave Receivers with HI-Z 500 Ohm Antenna Terminals.
-How- Connect the Antenna Terminals to the Receiver.
RIGGING - Tape and Thumb-Tacks will hold it in place.
SOURCES - Folded Dipole Antenna for FM Radio
RadioShack Catalog # 42-2385
http://www.radioshack.com/product/index.jsp?productId=2062691
* Horizontal Arms Tip-to-Tip 58-60 Inches across
* Vertical Feed-in-Line 72 Inches long
IMAGE => http://tinyurl.com/melg5
IMAGES => http://tinyurl.com/m2qaz
Alternative Links => http://tinyurl.com/pfvcr
http://tinyurl.com/rkcro
http://tinyurl.com/pldul
http://tinyurl.com/n76xa
eBay FM Dipole Antenna => http://tinyurl.com/mzoth
BUT BUT BUT ! - IT'S TOO SHORT FOR SHORTWAVE !
YES - That is Right - So for Shortwave use this FM Folded
Dipole Antenna is simply a Bent-Thin-Compresed Random Wire
Antenna that terminates to itself effectively forming a Loop.
- What Again ? - Well it is not 'cut' for any Shortwave
Frequency and will be used across the Shortwave Bands :
So it "IS" a Random Wire Antenna for this application.
- Why Is It A Loop ? - The FM Folded Dipole Antenna is
connected to {Starts at} one side of the Radio's Antenna
Input and is also is connected to {Ends at} the other side
of the Radio's Antenna Input forming a Bent-Thin-Compressed
Loop.
- Little But Long - What really matters is that at :
72" Out + 30" Out + 60" Across + 30" In + 72" In = 264"
which adds-up-to 22 Feet of Wire in the FM Folded Dipole
Antenna - And Hey one of those Reel {Roll-Up} Portable
Shortwave Antennas has about 23 Feet of Wire in them.
- Bigger than the Whip - Most Whip Antennas that are built
into the average 'portable' AM / FM Shortwave Radios are
about 28" to 42" long and very thin. If you wanted to
assign them an Area-of-Space that they occupied it would
be rather small 1" X 28"-42" = 28-42 Square Inches.
-But- Now the FM Folded Dipole when it is layed-out on
a Wall in the "T" Shape actually defines a Triangle 60"
Across the Top with a Vertical Demension of 72" = 2160
Square Inches. The FM Folded Dipole clearly has a
greater Signal Capture Area then the Whip Antenna.
FWIW - The simplest In-Door Antenna is the Folded Dipole.
http://www.kqed.org/help/radio/radio-tips.jsp
The Folded Dipole Antenna is frequently packed with new
AM/FM Radios. It is fabricated from Flat Television
Antenna Lead-in Material (often called Twin-Lead).
Twin-Lead is the Flat Plastic-Covered Wire - usually Brown
or pinkish-clear in color. A Folded Dipole Antenna is in
the Shape of the Letter "T". The Horizontal Part (the Arms)
of the Letter is the actual Antenna. The Vertical Part
(the fee-in-line) of the Letter connects the Antenna to
the Radio/Receiver. Most often the Folded Dipole Antenna
is placed on a Wall with the Vertical feed-in-line going
straight-up the Wall; and both of the Arms Stretched-Out
in opposite directions Horizontally. Again looking like a "T".
Experiment - Try orienting the Arms of the Dipole in different
positions for best Reception. Sometimes best results may be
obtained when the Arms are Vertical or Sloping. Often, the
Antenna can be Taped or Thumb-Tacked to the Wall or to the
back of Furniture when a good location is found.
TIP - Placing the Antenna in front of a Window or Diagonally
across a Window often is a good location for the best Radio
Reception.
A Simple, Efficient TV Antenna
http://www.wfu.edu/~matthews/misc/dipole.html
"How To" - Make a Folded Dipole from Twin-Lead
http://www.kyes.com/antenna/antennatypes/twinlead.jpg
Note - Folded Dipoles can be made very small :o)
http://users.skynet.be/chricat/antennes/folded-dipole-z.jpg
General Dipole Antenna Info - Links
http://en.wikipedia.org/wiki/Dipole_antenna
http://www.cebik.com/vhf/fm1.html
http://www.qsl.net/w4sat/fdipole.htm
SUMMARY - The FM Folded Dipole Antenna
Easy-to-Build and Cheaper-to-Buy -and- for a simple
'passive' In-Door Shortwave Antenna - It Works !
Keeping It Simple And Practical - iane ~ RHF
.
Shortwave Listener Antennas => http://tinyurl.com/ogvcf
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SWL Antenna Group => http://tinyurl.com/ogvcf
.
The Shortwave Listener's Blessing :
SWL BLESSING => http://tinyurl.com/s2bjm
May You Never Tire of Listening to the Radio and Always
have Strong Signals and Noise Free Reception ~ RHF {ibid}
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/9233
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