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RHF December 23rd 03 07:43 PM

DAVE,

Concerning the BroomStick Antenna:
http://www.hard-core-dx.com/nordicdx.../bromstik.html
http://www.hard-core-dx.com/nordicdx...al/broom2.html
http://www.hard-core-dx.com/nordicdx.../tunestik.html
http://www.hard-core-dx.com/nordicdx.../tunstik2.html

IIRC: The 1.2kM of wire was wrapped on a piece of PVC Pipe
http://www.hard-core-dx.com/nordicdx...al/broom3.html
- - - "improved model is 6 m (18Ft) of 4 Inch OD PVC"
(Section of Well Lining that was over 18 Foot Long.)
= = = Effectively a 18 Foot Vertical Antenna.
"I mounted the 6 m (18Ft) portion vertically, and the 2.5 m (7.5 Ft)
section horizontally (a "reverted "L"" system). I added in my 250 m
(750 Ft) Random Long Wire (it was there, so why not use it?), grounded
the thing and in great anticipation, plugged it into the radio.
- - - The results were more than amazing." - by Marty Leipzig

HELLO! Forget the BroomStick [.]
TBL: This Guy had a 750 Ft Random Wire Antenna !

When your 'think' of a Broom Stick Antenna that has a size small
wire tightly wrapped along a length of PVC Pipe. Just consider
the piece of PVC Pipe an equal section of Aluminum Tubing; and
not much more.

Better to try a Eight Foot Section of 2"-3" PVC Pipe with a
single wire wrapped in three coils on it.
* Use a 500 Foot Spool of #14 AWG Insulated 19 Stranded Wire.
* Each "Coil" set to resonate at a different band of your choice.
* Each "Coil" spaced 1'-2' apart on the PVC Pipe.

IMHO: The BrommStick Antenna is a 'good idea' for Apartment
Residents stuck with a single outside facing window.
- - - Been There, Done That !

REMEMBER: The ANTENNA + GROUND SYSTEM is . . .
55.5% of the Radio/Receiver and Antenna+Ground Reception Equation.
GoTo= http://groups.yahoo.com/group/SWL-AM...na/message/288

All are WELCOME at this "Antenna Ashram"
+ Who Seek Better Reception
+ + And a Clear Understanding
+ + + From That Which Transcends the Ether and Beyond.

WHE "SWL Antennas and AM & FM Antennas" eGroup on YAHOO !
- When You NEED to Contemplate the
- - "Aerial High" and the
- - - "True Meaning of Ground".


iane ~ RHF
..
..
= = = "Dave"
= = = wrote in message ...
I just got through picking up a ton of discontinued wire from my local Home
Depot, and was planning on building a "broomstick" antenna like some I found
described on the net. Got a question though: doesn't "stretching out" the
coil to a meter or more reduce the inductance of the resulting coil? Why
wouldn't it work better to just leave it on the spool? I was under the
impression that the formula for calculating the inductance for a given coil
involved multiplying the square of the number of coils by the ratio of the
coil width to length. Wouldn't this mean that a "longer" coil would have a
lower inductance than a "shorter" coil, given the same length of wire and
approximate diameter of coils?

Forgive me if I'm being stupid here, it has been twenty years since I have
attempted anything like this, but that was what I thought.

The main account I am thinking of was related by someone in Saudi Arabia who
wrapped 1.2 kM of wire around a piece of PVC and vastly improved their
reception of WWV in the states. I was going to do something similar, and
then looked at the two spools of wire that I was about to unwrap. They are
already coils, so shouldn't I be able to just hook them up to an aligator
clip and stick this to my whip antenna? (I am now thinking about taking the
wire off of the smaller spool and adding it to the larger. Shouldn't that
work?) And if I leave the wire on the spools (which are plastic) couldn't I
turn them toward or away from the station of interest to further improve
reception? (I could even put this in my attic, gaining a few feet of
elevation and hiding it from my unappreciative wife.)

Any input on any part of this idea is more than welcome. I would greaty
value the opinions of those who have actually done something like one of
these two options.

Thanks,

Dave


..

RHF December 23rd 03 07:48 PM

TM,

Good Accessment of the BroomStick Antenna.

iane ~ RHF
..
..
= = = Tony Meloche
= = = wrote in message ...
CW wrote:

I won't go into detail but the broomstick (or any helicaly wound antenna)
gives up performance for size. The straiter the wire, the better off you
are. If you have the space, just stretch it out strait.



Experimentation and experience have taught me that this is
basically correct. "Broomstick" antennas give pretty good performance
in a very compact space - they are even (marginally) "portable". But
for signal-pulling ability, they'll never beat a well-thought-out
longwire or randomwire. If you can tuck a one-meter broomstick into
your car somewhere for traveling, you've got the world
by the butt for shortwave listening away from home. But at home - your
"permanent space" - go with a random or longwire, if you possibly can.

Tony

..

RHF December 23rd 03 08:40 PM

= = = "Dave"
= = = wrote in message ...

Hmm. Okay. Only I don't have much outside space available.
I *might* be able to manage 20-30 feet of random wire, but
that is about it.


=R= Assuming that his is NOT a Metal Fence.

Another: [Hidden] "On-the-Fence" Random Wire Antenna

HOW TO: Use a short section of Fence for a
Low Level "Folded" Random Wire Antenna.

* Run a Coax Cable out to the Bottom of the Fence.
(Can be TV type 75 Ohm Coax Cable)

* Install a Ground Rod / Ground Wire HERE.
(If you have a Metal Fence Post Anchors ?
Use One as the Ground Point.)

* Use a Matching Transformer to connect the Antenna Element
to the Coax Cable.
(This can be a TV type 30075 Ohm Matching Transformer.

* Route the "WIRE" (Antenna Element) from the Starting-End of
the Fence; about one foot above and paralell to the ground to
the Far-End of the Fence.
* * Then go "UP" Vertically for about a foot.
* * Next route the Wire parallel to the ground; back to the
Starting-End of the Fence.
* * Then go "UP" Vertically for about a foot.
* * Next route the Wire parallel to the ground; back to the
Far-End of the Fence.
* * Then go "UP" Vertically for about a foot.
* * Next route the Wire parallel to the ground; back to the
Starting-End of the Fence.
* * Then go "UP" Vertically for about a foot.
* * Next route the Wire parallel to the ground; back to the
Far-End of the Fence.
= = = 100Ft - 150Ft Random Wire Antenna
(5 X 20Ft = 100Ft -&- 5 X 30Ft = 150Ft)

Sorta - Looka - Lika - Diz:
_____________________________x
|____________________________
_____________________________|
|____________________________
===MT________________________|
....G.........................

..
..
And I have more than a mile of small-guage wire on these two
spools. I was planning on wrapping it around a five-foot long
piece of 4 inch PVC and standing it behind a closet door.


=R= Better to wrap the wire Length-Wise 'inside & out'
(over and through) the PVC Pipe with about 1" spacing.
This would be about 120 Ft of wire in a vertical format.

..
..
Since my last last message I tried a very crude "hook-up" with
one of the spools of wire and got absolutely no improvement
in reception. Now I understand why, thanks to you good people.

Back to the 20-30' piece of random wi my only option is to
run it out the window and along the top rail of the fence in
the back yard. Would this really outdo a massive broomstick
antenna ?


=R= ? QUESTION ? "Top Rail" Is this a Metal Fence ?

..
..
Thanks for the input. You've all got me thinking.

Dave




iane ~ RHF

..

..

Brenda Ann December 23rd 03 08:40 PM


"Dave" wrote in message
...

Okay, so here's the problem. The fence is metal, and the house is covered
with steel siding. My DX-402 does pick up BBC on 5975 pretty well with

just
the whip (next to a window), but VOK is extremely weak to vanishing.

(This
last one is what I want the broomstick antenna for.) If I do go with the
broomstick, should I stick with the five-foot piece that I already have

cut,
or go with a longer eight-foot piece which will still fit nicely in the
corner I have in mind. Or should I go all out with a ten-foot piece (or
even multiples maybe) and put it in the attic? Also, what type of ground
should I use? I could run a ground wire out the window to a ground rod

that
is as old as the house, but that's about my only option (the house

predates
three-prong plugs with a real ground.)

I really appreciate your thoughts on these things. You obviously know a

lot
more about this stuff than I do.


The rafters idea could still work with standoffs, though not as well as with
a wood surface. What material is your roof made from? How much of a crown
does it have? You could run wire along the crown of the roof with good
results. Use coax to get it into the house. Ground the coax outside the
house at the point it enters.



donutbandit December 23rd 03 10:04 PM

"Dave" wrote in
:

I just got through picking up a ton of discontinued wire from my local
Home Depot, and was planning on building a "broomstick" antenna like
some I found described on the net.


I built one. I was quite disappointed after reading all the hype.

I get better reception from a wire run around the corners of my
bedroom ceiling.

Dale Parfitt December 23rd 03 10:50 PM


"donutbandit" wrote in message
...
"Dave" wrote in
:

I just got through picking up a ton of discontinued wire from my local
Home Depot, and was planning on building a "broomstick" antenna like
some I found described on the net.


I built one. I was quite disappointed after reading all the hype.

I get better reception from a wire run around the corners of my
bedroom ceiling.

I woul not anticipate the broomstick antenna to be any different than a
metal tube or rod of similar dimensions.

Dale W4OP



funkbastler December 23rd 03 11:12 PM

On 23 Dec 2003 14:27:39 GMT, (Diverd4777) wrote:

Brenda et al:

This statement facinates me:

related by someone in Saudi Arabia
who
wrapped 1.2 kM of wire around a piece of PVC and vastly improved their
reception of WWV in the states.


1.2 kM of wire; Heck of a lot of capture area !


Very little capture area if it's all coiled up in a small space.


Is there some ratio of loop diameter and spacing between the wire loops that
results in the most capture area?


The bigger the diameter, the bigger the capture area.


There is a nice ratio of mirror diameter to magnification limits in telescopes
This is the analogy I was thinking of.


Yes, but what you'd be concerned with here is 'light gathering power'
(aka aperture), not magnification.


Dan


-fb-


Telamon December 24th 03 12:28 AM

In article ,
"Dale Parfitt" wrote:

"donutbandit" wrote in message
...
"Dave" wrote in
:

I just got through picking up a ton of discontinued wire from my
local Home Depot, and was planning on building a "broomstick"
antenna like some I found described on the net.


I built one. I was quite disappointed after reading all the hype.

I get better reception from a wire run around the corners of my
bedroom ceiling.


I would not anticipate the broomstick antenna to be any different than
a metal tube or rod of similar dimensions.


Good comparison. A tightly wound broomstick would resemble a rod for
receiving purposes.

--
Telamon
Ventura, California

Dave December 25th 03 06:54 AM


"Diverd4777" wrote in message
...
In article , "Dave"


writes:

Or should I go all out with a ten-foot piece of 4 inch PVC (or
even multiples maybe) and put it in the attic?


If the attic is non-metal, I'd try this solution ..


Sorry it took me so long to reply. Christmas, and all.

The attic/roof is not-metal, but it is so short that you really can't move
around in it. I can stick something up there and more-or-less angle it this
way or that, but that's about it. I thought about putting something
directional up there, but upon further reflection I really don't see any way
to do that. And outside, I could run a wire along the top of the (metal)
fence, but that's about it. Thought about putting something under the
eaves, and haven't totally given up on that yet. If I did that, I could
make it +/- 30 feet long. Still thinking.

Thanks for the input.

Dave





Dave December 25th 03 07:09 AM


"Brenda Ann" wrote in message
...

"Dave" wrote in message
...

Okay, so here's the problem. The fence is metal, and the house is

covered
with steel siding. My DX-402 does pick up BBC on 5975 pretty well with

just
the whip (next to a window), but VOK is extremely weak to vanishing.

(This
last one is what I want the broomstick antenna for.) If I do go with

the
broomstick, should I stick with the five-foot piece that I already have

cut,
or go with a longer eight-foot piece which will still fit nicely in the
corner I have in mind. Or should I go all out with a ten-foot piece (or
even multiples maybe) and put it in the attic? Also, what type of

ground
should I use? I could run a ground wire out the window to a ground rod

that
is as old as the house, but that's about my only option (the house

predates
three-prong plugs with a real ground.)

I really appreciate your thoughts on these things. You obviously know a

lot
more about this stuff than I do.


The rafters idea could still work with standoffs, though not as well as

with
a wood surface. What material is your roof made from? How much of a crown
does it have? You could run wire along the crown of the roof with good
results. Use coax to get it into the house. Ground the coax outside the
house at the point it enters.



The roof is wood with asphalt shingles. But the attic is only about three
feet tall (see my reply to diverd4777). With extreme difficulty one can get
from one side of the house to the other through the attic, but trying to do
this while carrying something is next to impossible. Is that what you are
asking about, about the crown? Height, in the attic? If not please let me
know.

Dave





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