Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Old October 28th 05, 11:36 PM
RC
 
Posts: n/a
Default SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna for Shortwave Listening

What diameter of PVC pipe are you using, and does the slink go inside
or outside the pipe?
RHF wrote:
So Like I Had This Idea and Wow !
.
What About a Multi-Band "Off-Center" Vertical Dipole Antenna
made from a Single (one) Slinky for Shortwave Listening ?
http://groups.yahoo.com/group/Shortw...a/message/5696
.
Building the Multi-Band "Off-Center" Vertical Dipole Antenna :
.
Get an Eight Foot Piece of PVC Pipe as your Vertical Antenna
Form and a Stabdard Size Slinky.
.
NOTE - 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.
* Optimum "Stretched-Out" Length about 22.9 Feet
.
Drill Four (4) Holes through both sides of the PVC Pipe.
Hole # 1 - One an Inch from the Bottom
Hole # 2 - One 36 Inches from the Bottom
Hole # 3 - One 37 Inches from the Bottom
Hole # 4 - One an Inch from the Top
.
Take a Standard Size SLINKY and starting at one end count-off
36 turns and Cut the Slinky at this point. You now have two
pieces of Slinky one shorter piece with 36 Turns and the other longer
piece with about 64 Turns.
.
Take the piece of Slinky with the 36 Turns and place on
the piece of PVC Pipe (pipe going thru the 35 Turns of
the Slinky) and then thread one end thru Hole # 1 and
Bend that End to lock it in place.
.
Stetch-Out this 35 Turn piece of Slinky so that the other
end can be threaded thru Hole # 2 and Bend that End to
lock it in place.
.
Take the piece of Slinky with the 64 Turns and place on
the piece of PVC Pipe (pipe going thru the 64 Turns of
the Slinky) and then thread one end thru Hole # 4 and
Bend that End to lock it in place.
.
Stetch-Out this 64 Turn piece of Slinky so that the other
end can be threaded thru Hole # 3 and Bend that End to
lock it in place.
.
Now connect or Solder the Leads of a TV type 300 Ohm to
75 Ohm Matching Transformer to the Bent Ends of the Slinky
coming out of Holes # 2 and # 3.
.
Place an End-Cap on both ends of the PVC Pipe.
.
Mount the Multi-Band "Off-Center" Vertical Dipole Antenna :
InDoors in a Corner; OutSide Hanging from the Eaves; Mounted
to the Chimney; or setting on top of a piece of Top-Rail.
.
Connect a 75 Ohm Coax Cable (RG6 Quad-Shield) to the
Matching Transformer and down to your Radios.
.
ALT # 1 - Use a Longer-Wider piece of PVC Pipe :
Ten Foot (120 Inches) piece of PVC Pipe.
Drill Four (4) Holes through both sides of the PVC Pipe.
Hole # 1 - One an Inch from the Bottom
Hole # 2 - One 45 Inches from the Bottom
Hole # 3 - One 46 Inches from the Bottom
Hole # 4 - One an Inch from the Top
.
ALT # 2 - Use a Smaller-Shorter Size Slinky :
Slinky Jr. {Junior} which has about 85 Turns with a Diameter
of 1 7/8 Inches and a Circumference of 5.89 Inches for a
Total Wire Length of "41.7" Feet.
* Optimum "Stretched-Out" Length about 13.3 Feet
Therefore - The Bottom piece of Slinky Jr. would be 32 Turns
and the Top piece would be 53 Turns.
.
.
iane ~ RHF
.
All are WELCOME and "Invited to Join" the
Shortwave Listener (SWL) Antenna eGroup on YAHOO !
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SWL ANTENNAS GROUP = http://tinyurl.com/an6tw
.
Some Say: On A Clear Day You Can See Forever.
http://groups.yahoo.com/group/Shortw...na/message/502
.
I BELIEVE: On A Clear Night . . .
You Can Hear Forever and Beyond, The BEYOND !
With a Shortwave Listener SWL Antenna of your own making.
"If You Build It {SWL Antenna} You Will Hear Them !"
.
.
. .


  #2   Report Post  
Old October 29th 05, 12:07 PM
RHF
 
Posts: n/a
Default SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna for Shortwave Listening

RC,

I use 3/4" Schedule 40 White PVC Pipe.
http://www.harvel.com/pipepvc-sch40-80-dim.asp
SIZE = 3/4" / OD = 1.050 / ID = 0.804
WT = 0.113 / Lbs/Ft = 0.226

It Works Like This :
The 2.75 Inch Slinky goes over the 1.05" PCV Pipe.

Hey - Just for Fun - Take the Pipe and slant it at an angle
place the Slinky at the Top-End over the Pipe and let it
slide down - - - Gee this is Fun ) !

UPDATING THE DESIGN : {ADDENDUM} PART II OF THE
SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna
for Shortwave Listening.
http://groups.yahoo.com/group/Shortw...a/message/6094

A 'second' build of this Off-Center-Fed Dipole Antenna
had me use a Ten Foot (120") piece of PVC Pipe to use
the Bottom 17 Inches as the Mounting Section. Plus a
way to Route the Coax Cable Feed-in-Line 'through' the
PVC Pipe vice having it hang on the outside of the Pipe.
So I added a 'new' 3/8" Hole in the PVC Pipe for the Leads
of the Matching Transformer to pass through.

Building the PVC Pipe Antenna Form :
The Ends of the 'cut' Slinky go through the Holes that you
Drill in the Pipe. Drill Four (4) 1/8" Holes through both
sides of the PVC Pipe :
Hole # 1 - One an 17 Inches from the Bottom
Hole # 2 - One 53 Inches from the Bottom
Hole # 3 - One 55 Inches from the Bottom
Hole # 4 - One 119 Inches from the Bottom (1" Top)
Align all Four (4) Holes up along the length of the Pipe.
Plus One 3/8" Hole aligned on One-Side-Only at 54 Inches
from the Bottom for the Feed-in-Line.

Note - Only put a PVC "Cap" on the Top End of this Ten Foot
piece of PVC Pipe to seal the Top from Weather.

Pre-Assembly :
The TV Matching Transformer is connected to the RG6 Quad
Shield Coax Cable. A Fish Line is then fed through the
3/8" Hole and down to the Bottom of the Pipe. The Leads
of the Matching Transformer are pulled up through the 3/8"
Hole.
Note - This places the Matching Transformer and the Coax Cable
Feed-in-Line inside {Hidden in] the PVC Pipe.

Making and Rigging the Antenna Elements :
The Slinky is 'cut' at Turn (Coil) # 36 and you have two
pieces of Slinky :
- One shorter piece with about 36 Turns.
Stretch this one between Holes #1 and #2; and Thread the
each of the Ends into the nearest Hole; then Bend the Tips
over to Secure Ends of the piece of Slinky.
- One longer piece with about 64 Turns
Stretch this one between Holes #3 and #4; and Thread the
each of the Ends into the nearest Hole; then Bend the Tips
over to Secure Ends of the piece of Slinky.

Making the Connection :
Connect the 300 Ohm Leads of the Matching Transformer to
the upper and lower Ends of the Slinky coming out of Holes
#2 and #3. Twist the Lead Wires around the Bent Ends of
the Slinky and Solder them to from a solid joint.

Weather Proofing the Antenna :
Seal all the Holes made in the PVC Pipe.
The Bottom can simply be 'plugged' with Foam.

Mounting the PVC Pipe :
Two Hose Clamps a Foot apart on top of a piece of Top-Rail
works great. One Inch up from the Bottom; Two Hose Clamps
about 12 Inches apart; with about 4 Inches between the Top
of the Top-Rail (Mast) and the Bottom Coil of the Slinky.
- Place the Top-Rail along side the House and secure it.
- Or stick a few feet of the Top-rail in the ground in
the Yard.
Another "Field-Day" Option is to use a 4'-6' Foot piece
of Re-Bar pounded half-way into the ground and then use
two Hose Clamps about a Foot apart to hold the PVC Pipe
bottom about a foot or two above the ground and securely
in an up-right position. (This should result in having
the Bottom Slinky Coil about 4"-6" above the Top of the
Re-bar.)

The Hook-Up to the Radio/Receiver :
* Radios with an 1/8" External Antenna Input Jack.
Use a 90* Elbow "F" Connector with an "F" Connector to
1/8" Mono Plug 'Adapter'.
* Receivers with an SO-239 External Antenna Input Jack.
Use an "F" Connector to PL-259 Plug 'Adapter'.

TIP - To make this 'Limited Space' Off-Center-Fed Verical
Dipole Antenna work better; try using an Active Pre-Selector
with it; between the Antenna and the Radio.

All of these Active {In-Door} Antennas can be used as a
"Pre-Selector" with good results with a 'short' External
Antenna mounted free and clear on the outside of the
House above the Roof or out in the yard.

* Ameco Tunable Pre-Amplifier Antenna (TPA)
http://www.universal-radio.com/catalog/sw_ant/1512.html

* MFJ-1020C In-Door Active Antenna
http://www.universal-radio.com/catalog/sw_ant/1413.html
- MFJ-959C Pre-Amplifier and Antenna Tuner
http://www.universal-radio.com/catal...amps/2574.html
- MFJ-1040C Active Pre-Selector
http://www.universal-radio.com/catal...amps/4110.html
- MFJ-1045C Receiver Pre-Selector
http://www.universal-radio.com/catal...amps/0807.html

* Palstar AA30 Portable Active Receiving Antenna
http://www.universal-radio.com/catalog/sw_ant/1492.html

* Vectronics AT-100 Portable Active Antenna
http://www.universal-radio.com/catalog/sw_ant/3059.html


that's all folks - iane ~ RHF
  #3   Report Post  
Old October 30th 05, 01:39 AM
Telamon
 
Posts: n/a
Default SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna for Shortwave Listening

In article .com,
"RHF" wrote:

RC,

I use 3/4" Schedule 40 White PVC Pipe.
http://www.harvel.com/pipepvc-sch40-80-dim.asp
SIZE = 3/4" / OD = 1.050 / ID = 0.804
WT = 0.113 / Lbs/Ft = 0.226

It Works Like This :
The 2.75 Inch Slinky goes over the 1.05" PCV Pipe.


snip

Nothing wrong with using the pipe but you could use nylon cord just as
well. The cord should be easer to use than the pipe.

--
Telamon
Ventura, California
  #4   Report Post  
Old November 1st 05, 12:34 AM
RC
 
Posts: n/a
Default SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna for Shortwave Listening

Maybe I'm just dense, but I'm having a hard time visualizing the Slinky
attenna. Do you have any drawings, detail diagrams, or pictures of it?
RHF wrote:
RC,

I use 3/4" Schedule 40 White PVC Pipe.
http://www.harvel.com/pipepvc-sch40-80-dim.asp
SIZE = 3/4" / OD = 1.050 / ID = 0.804
WT = 0.113 / Lbs/Ft = 0.226

It Works Like This :
The 2.75 Inch Slinky goes over the 1.05" PCV Pipe.

Hey - Just for Fun - Take the Pipe and slant it at an angle
place the Slinky at the Top-End over the Pipe and let it
slide down - - - Gee this is Fun ) !

UPDATING THE DESIGN : {ADDENDUM} PART II OF THE
SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna
for Shortwave Listening.
http://groups.yahoo.com/group/Shortw...a/message/6094

A 'second' build of this Off-Center-Fed Dipole Antenna
had me use a Ten Foot (120") piece of PVC Pipe to use
the Bottom 17 Inches as the Mounting Section. Plus a
way to Route the Coax Cable Feed-in-Line 'through' the
PVC Pipe vice having it hang on the outside of the Pipe.
So I added a 'new' 3/8" Hole in the PVC Pipe for the Leads
of the Matching Transformer to pass through.

Building the PVC Pipe Antenna Form :
The Ends of the 'cut' Slinky go through the Holes that you
Drill in the Pipe. Drill Four (4) 1/8" Holes through both
sides of the PVC Pipe :
Hole # 1 - One an 17 Inches from the Bottom
Hole # 2 - One 53 Inches from the Bottom
Hole # 3 - One 55 Inches from the Bottom
Hole # 4 - One 119 Inches from the Bottom (1" Top)
Align all Four (4) Holes up along the length of the Pipe.
Plus One 3/8" Hole aligned on One-Side-Only at 54 Inches
from the Bottom for the Feed-in-Line.

Note - Only put a PVC "Cap" on the Top End of this Ten Foot
piece of PVC Pipe to seal the Top from Weather.

Pre-Assembly :
The TV Matching Transformer is connected to the RG6 Quad
Shield Coax Cable. A Fish Line is then fed through the
3/8" Hole and down to the Bottom of the Pipe. The Leads
of the Matching Transformer are pulled up through the 3/8"
Hole.
Note - This places the Matching Transformer and the Coax Cable
Feed-in-Line inside {Hidden in] the PVC Pipe.

Making and Rigging the Antenna Elements :
The Slinky is 'cut' at Turn (Coil) # 36 and you have two
pieces of Slinky :
- One shorter piece with about 36 Turns.
Stretch this one between Holes #1 and #2; and Thread the
each of the Ends into the nearest Hole; then Bend the Tips
over to Secure Ends of the piece of Slinky.
- One longer piece with about 64 Turns
Stretch this one between Holes #3 and #4; and Thread the
each of the Ends into the nearest Hole; then Bend the Tips
over to Secure Ends of the piece of Slinky.

Making the Connection :
Connect the 300 Ohm Leads of the Matching Transformer to
the upper and lower Ends of the Slinky coming out of Holes
#2 and #3. Twist the Lead Wires around the Bent Ends of
the Slinky and Solder them to from a solid joint.

Weather Proofing the Antenna :
Seal all the Holes made in the PVC Pipe.
The Bottom can simply be 'plugged' with Foam.

Mounting the PVC Pipe :
Two Hose Clamps a Foot apart on top of a piece of Top-Rail
works great. One Inch up from the Bottom; Two Hose Clamps
about 12 Inches apart; with about 4 Inches between the Top
of the Top-Rail (Mast) and the Bottom Coil of the Slinky.
- Place the Top-Rail along side the House and secure it.
- Or stick a few feet of the Top-rail in the ground in
the Yard.
Another "Field-Day" Option is to use a 4'-6' Foot piece
of Re-Bar pounded half-way into the ground and then use
two Hose Clamps about a Foot apart to hold the PVC Pipe
bottom about a foot or two above the ground and securely
in an up-right position. (This should result in having
the Bottom Slinky Coil about 4"-6" above the Top of the
Re-bar.)

The Hook-Up to the Radio/Receiver :
* Radios with an 1/8" External Antenna Input Jack.
Use a 90* Elbow "F" Connector with an "F" Connector to
1/8" Mono Plug 'Adapter'.
* Receivers with an SO-239 External Antenna Input Jack.
Use an "F" Connector to PL-259 Plug 'Adapter'.

TIP - To make this 'Limited Space' Off-Center-Fed Verical
Dipole Antenna work better; try using an Active Pre-Selector
with it; between the Antenna and the Radio.

All of these Active {In-Door} Antennas can be used as a
"Pre-Selector" with good results with a 'short' External
Antenna mounted free and clear on the outside of the
House above the Roof or out in the yard.

* Ameco Tunable Pre-Amplifier Antenna (TPA)
http://www.universal-radio.com/catalog/sw_ant/1512.html

* MFJ-1020C In-Door Active Antenna
http://www.universal-radio.com/catalog/sw_ant/1413.html
- MFJ-959C Pre-Amplifier and Antenna Tuner
http://www.universal-radio.com/catal...amps/2574.html
- MFJ-1040C Active Pre-Selector
http://www.universal-radio.com/catal...amps/4110.html
- MFJ-1045C Receiver Pre-Selector
http://www.universal-radio.com/catal...amps/0807.html

* Palstar AA30 Portable Active Receiving Antenna
http://www.universal-radio.com/catalog/sw_ant/1492.html

* Vectronics AT-100 Portable Active Antenna
http://www.universal-radio.com/catalog/sw_ant/3059.html


that's all folks - iane ~ RHF
.
.
All are WELCOME and "Invited to Join" the
Shortwave Listener (SWL) Antenna eGroup on YAHOO !
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SWL ANTENNAS GROUP = http://tinyurl.com/an6tw
.
Some Say: On A Clear Day You Can See Forever.
http://groups.yahoo.com/group/Shortw...na/message/502
.
I BELIEVE: On A Clear Night . . .
You Can Hear Forever and Beyond, The BEYOND !
With a Shortwave Listener SWL Antenna of your own making.
"If You Build It {SWL Antenna} You Will Hear Them !"
.
.
. .
.


  #5   Report Post  
Old November 1st 05, 06:36 AM
RHF
 
Posts: n/a
Default SLINKY - Multi-Band "Off-Center" Vertical Dipole Antenna for Shortwave Listening

RC - As stated in a prior message :

" It Works Like This :
The 2.75 Inch Slinky goes over the 1.05" PCV Pipe. "

~ RHF
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
Inverted ground plane antenna: compared with normal GP and low dipole. Serge Stroobandt, ON4BAA Antenna 8 February 24th 11 11:22 PM
suggestions for a limited space HF antenna.. vertical or dipole Dan Antenna 4 May 28th 04 01:32 PM
Mobile Ant L match ? Henry Kolesnik Antenna 14 January 20th 04 05:08 AM
Poor quality low + High TV channels? How much dB in Preamp? lbbs Antenna 16 December 13th 03 04:01 PM
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 08:33 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 RadioBanter.
The comments are property of their posters.
 

About Us

"It's about Radio"

 

Copyright © 2017