Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old September 24th 05, 04:00 PM
RHF
 
Posts: n/a
Default How Long Should My "Slinky" Dipole Antenna BE ? - - - How Many Slinkys You Got ?

For One and All,
  #2   Report Post  
Old September 24th 05, 10:46 PM
Telamon
 
Posts: n/a
Default

In article . com,
"RHF" wrote:

For One and All,
.
How Long Should My Slinky Antenna BE ?
- - - How Many Slinkys You Got ?
http://groups.yahoo.com/group/Shortw...a/message/5411
.
The standard Full Size Slinky has about 100 Turns with a
Diameter of 2 3/4 Inches and a Circumference of 8.64 Inches
for a Total Wire Length of 72 Feet.
.
So the Optimum* "Stretched-Out" Length of a Slinky would
be about 22.9 Feet. * Note - Based on the "Spacing" of
the Coil being 'equal' to the Diameter of the Coil.
.
.
SIZING THE SLINKY DIPOLE ANTENNA :
.
A Two (2) Slinky Dipole (1 Slinky per Arm of the Dipole)
would be about 45.8 Feet Tip-to-Tip; and that would be
Resonant about 10.6 MHz. Rig the Dipole Antenna at about
23 Feet above Ground.
.
A Three (3) Slinky Dipole (1.5 Slinkys per Arm of the
Dipole) would be about 68.7 Feet Tip-to-Tip and that
would be Resonant about 7 MHz. Rig the Dipole Antenna
at about 34 Feet above Ground.
.
A Four (4) Slinky Dipole (2 Slinkys per Arm of the Dipole)
would be about 91.6 Feet Tip-to-Tip; and that would be
Resonant about 5.3 MHz. Rig the Dipole Antenna at about
46 Feet above Ground.
.
A Six (6) Slinky Dipole (3 Slinkys per Arm of the Dipole)
would be about 137.4 Feet Tip-to-Tip; and that would be
Resonant about 3.5 MHz. Rig the Dipole Antenna at about
69 Feet above Ground.
.
Any Comments and Corrections ?
[ No Rock Throwing - Please ! ]


Snip

I don't think that using a slinky is very good antenna. You might as
well use a straight wire.

You would be better off using a minimum of three or more parallel wires
through spacers to approximate a cylinder shape. The more parallel wires
you use the bigger the diameter of the cylinder could be.

Using a slinky is convenient and what I advocated above would be a lot
more trouble to make but it would work better.

I haven't owned a slinky since I was a kid.

--
Telamon
Ventura, California
  #3   Report Post  
Old September 25th 05, 12:33 AM
RHF
 
Posts: n/a
Default

Telamon - Speaking of Slinkys and Antennas . . .
It is just an Idea that I have been Toying with :-P
  #4   Report Post  
Old September 25th 05, 12:34 AM
BDK
 
Posts: n/a
Default

In article telamon_spamshield-1C4297.14462524092005
@newsclstr02.news.prodigy.com,
lid says...
In article . com,
"RHF" wrote:

For One and All,
.
How Long Should My Slinky Antenna BE ?
- - - How Many Slinkys You Got ?
http://groups.yahoo.com/group/Shortw...a/message/5411
.
The standard Full Size Slinky has about 100 Turns with a
Diameter of 2 3/4 Inches and a Circumference of 8.64 Inches
for a Total Wire Length of 72 Feet.
.
So the Optimum* "Stretched-Out" Length of a Slinky would
be about 22.9 Feet. * Note - Based on the "Spacing" of
the Coil being 'equal' to the Diameter of the Coil.
.
.
SIZING THE SLINKY DIPOLE ANTENNA :
.
A Two (2) Slinky Dipole (1 Slinky per Arm of the Dipole)
would be about 45.8 Feet Tip-to-Tip; and that would be
Resonant about 10.6 MHz. Rig the Dipole Antenna at about
23 Feet above Ground.
.
A Three (3) Slinky Dipole (1.5 Slinkys per Arm of the
Dipole) would be about 68.7 Feet Tip-to-Tip and that
would be Resonant about 7 MHz. Rig the Dipole Antenna
at about 34 Feet above Ground.
.
A Four (4) Slinky Dipole (2 Slinkys per Arm of the Dipole)
would be about 91.6 Feet Tip-to-Tip; and that would be
Resonant about 5.3 MHz. Rig the Dipole Antenna at about
46 Feet above Ground.
.
A Six (6) Slinky Dipole (3 Slinkys per Arm of the Dipole)
would be about 137.4 Feet Tip-to-Tip; and that would be
Resonant about 3.5 MHz. Rig the Dipole Antenna at about
69 Feet above Ground.
.
Any Comments and Corrections ?
[ No Rock Throwing - Please ! ]


Snip

I don't think that using a slinky is very good antenna. You might as
well use a straight wire.

You would be better off using a minimum of three or more parallel wires
through spacers to approximate a cylinder shape. The more parallel wires
you use the bigger the diameter of the cylinder could be.

Using a slinky is convenient and what I advocated above would be a lot
more trouble to make but it would work better.

I haven't owned a slinky since I was a kid.




The slinky windom I had was far superior to any commercial or any other
antenna I have ever had. Huge signal strength. I used to run my radios
with an AM BCB killer to keep the nearby AM station on 1560 from causing
problems due to huge (big enough that 20DB attenuation wasn't even close
to unpegging the S-Meter, it took 80 at least) signals getting into the
receiver. I still have those AM killers I made back then, but haven't
had to use them on the slopers and dipole I have now.
There's a lot of length both physically and electrically. Your parellel
wire antenna would be a major hassle to make, and to keep together. The
slinky isn't.

And it was far cheaper than the Slopers and Eavesdroppers too. Not to
mention it lasted longer...nearly 15 years. I changed the rope and coax
every 5.

BDK
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Antenna Suggestions and Lightning Protection § Dr. Artaud § Shortwave 71 April 26th 05 04:14 PM
Imax ground plane question Vinnie S. CB 151 April 15th 05 05:21 AM
Poor quality low + High TV channels? How much dB in Preamp? lbbs Antenna 16 December 13th 03 03:01 PM
Question for better antenna mavens than I Tony Meloche Shortwave 7 October 28th 03 09:16 AM
QST Article: An Easy to Build, Dual-Band Collinear Antenna Serge Stroobandt, ON4BAA Antenna 12 October 16th 03 07:44 PM


All times are GMT +1. The time now is 05:58 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2025 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017