Shortwave Antenna
Paul
decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB.
Any advice would be helpful.
thanks,
Paul
Warpcore
Otherwise, buy 100 feet of hookup wire and rig it East-West and end-feed it
to your receiver via any tuners, preamps , matchers or preseleectors and you
should be alright. It won't hurt anything if you can only hang 50 to 75
feet, and if you don't have any of the aforementioned equipment, don't sweat
it .
The higher you can get it, the better. If it slants down, that is beneficial
for reducing noise.
If you find your receiver is over loading, reduce the length of the antenna.
Be sure your receiver is connected to a good ground as that improves
reception.
Reception has been poor recently. No amount of wire is going to improve
that, except to say, that a longer length of wire will receive more energy.
Some of that energy is going to be flourescent lights, power lines etc., so
keep that in mind.
I don't know where you are located geographically, but just go with the
flow. I got up at 1:30 AM PDT this morning and heard Australia from 2.310
pretty well, but other frequencies varied - I heard several Ecuadoreans and
Papua New Guinea, but the BBC Relay broadcast from Solomon Islands was
marred by interference from something I could not identify, and other
australian stations from Tennant Creek and Katherine did not fare so well,
but Papua New Guinea from Port Moresby did fine; I heard WLO very clearly as
well, giving weather synopses. It is all a gift, so enjoy what you can hear
<S>.
Paul
"Warpcore" <mky...@earthlink.net> wrote in message
news:mTv2b.3480$3E....@newsread3.news.pas.earthlink.net...
Warpcore
been so good lately.
Diverd4777
It's a nice looking gadget, but
50 - 150 feet of wire stretched e/w & far away from electrical appliances /
lines will do much better.
I find the 18 - 22 Gage Radio Shack Stranded insulated wire easiest to deal
with.
You can either hook the antenna up directly to you r whip antenna , or tape it
down 1/4 - 2 inches away from the whip if you get " Overload";
- Also disconnect the wire before a thunderstorm , etc..
Look hre for more info on Antennas & DX'ing
http://www.hard-core-dx.com/index.php?topic=antennas
Dan
In article <vkl1ak...@corp.supernews.com>, "Paul" <ti...@nospamaol.com>
writes:
Diverd4777
- Better link for shortwave antenna info......
http://www.hard-core-dx.com/nordicdx/antenna/wire/
In article <vkl1ak...@corp.supernews.com>, "Paul" <ti...@nospamaol.com>
writes:
>Mon, 25 Aug 2003 16:54:13 -0500
yachtboy!
Last night I spent a couple of hours trying to get Radio Cairo. Very bad
reception on a;; freq. Gave up and went to bed.
==========
"Being diabetic is alot like having an un-invited
guest at a picnic, who keeps pointing out the potato
salad may have gone bad."--W.B. Willis
"Destiny has a strange sense of humor..." K. Honeycutt
----------
http://www.geocities.com/swl_yb400pe
http://www.geocities.com/swl_yb400pe/psychedelic.htm
http://www.geocities.com/swl_yb400pe/slinkypage.html
"He not busy being born is busy dying..." B. Dylan
=======================
Dale Parfitt
Warpcore wrote:
> If it slants down, that is beneficial
> for reducing noise.
>
Can you explain why this is?
Dale W4OP
Kruppt
news:vkl1ak...@corp.supernews.com:
I have a few of these portable antennas I use with my portable Sangean
shortwaves,for listening, while watching my kids play at the park etc.
All they are is a wind-up long wire antenna. I have built lots of
differrent antennas over the years, and always fall back on the trusty
ole dipole antenna. Now that I have built all my antenna farms and have
tired of maintaining/building them, the simple ole dipole is it. After
you have learned to build it, install it, you can forget it. Spend your
time enjoying your radio and other, as the dipole is all you need. Still
listening after 20 years. Drake R8, Sangean 808, Sangean 803A, Sangean
606, Grove TUN-4, ......and down to one last 100' dipole 75' in the air,
may it last the rest of my life, I'm tired of erecting antennas! LOL!
Kruppt
Paul
dipole
"Kruppt" <Krup...@myrealbox.com> wrote in message
news:Xns93E2E1A264E00t...@63.223.5.101...
The Axelrods
There are some ideas at the AMANDX site below and some answers about propagation too.
--
73 and Best of DX
Shawn Axelrod
Visit the AMANDX DX site with info for the new or experienced listener:
http://www.angelfire.com/mb/amandx/index.html
REMEMBER ON A CLEAR DAY YOU CAN HEAR FOREVER
RHF
ON-POINT: For your USB 11.175 MHz a Half Wave Dipole (HWD) is a good
antenna but requires a specific length and height for a small band of
frequencies and for those frequencies is very directional.
* These facts limit the HWD's application as a good overall for the
other group of frequencies 5-9 MHz (USB).
* You could construct a Dual-Band HWD or Tri-Band HWD Antennas to try
and cover these three SW bands.
* Usually Multi-Band HWD Antennas are 'cut' for the lowest frequency
(longest/largest size).
* A type of HWD that uses a single center support with two slopping
legs is call the Inverted "V".
NOTE: The commercial antenna that goes by the Brand Name of "Alpha
Delta" Model "DX Ultra" (80Ft Long / 20-30Ft Center / 5-10Ft Ends) is
a Tri-Band Inverted "V" Antenna.
http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=Alpha+Delta+DX-ULTRA+&btnG=Google+Search
FWIW: You may wish to consider the a simple basic antenna that
incorporates the Low Noise Antenna Design Concepts a la John Doty.
http://groups.yahoo.com/group/SWL-AM-FM-Antenna/message/2
The best shape antenna that lends itself to the Low Noise Antenna
Design is the Inverted "L" Antenna.
http://groups.yahoo.com/group/SWL-AM-FM-Antenna/message/10
The Inverted "L" Antenna can be erected at any average Height 15-45
Feet and for any reasonable Length 30-135 Feet to fit your land and
space limitations. When constructed well using a matching transformer
and ground; they can give good omni-directional coverage across the
LW, AM/MW, and SW Bands.
~ RHF
.
.
= = = "Paul" <ti...@nospamaol.com>
= = = wrote in message news:<vkl1ak...@corp.supernews.com>...
TailGator
Florida, right on the water, and have an 80-ft longwire, end-fed, about 35
feet up and sloping down to a fence post. Coax to a Grove TUN-4 and an Icom
R75 and a Drake. Reception is fantastic! Can't go wrong with a long...wire,
that is:)
John
KF4ANC
"Paul" <ti...@nospamaol.com> wrote in message
news:vkl1ak...@corp.supernews.com...
starman
>
> Agree wholeheartedly with the dipole comments - I live on the Gulf coast of
> Florida, right on the water, and have an 80-ft longwire, end-fed, about 35
> feet up and sloping down to a fence post. Coax to a Grove TUN-4 and an Icom
> R75 and a Drake. Reception is fantastic! Can't go wrong with a long...wire,
> that is:)
What you have is a sloping inverted-L antenna. A real longwire is much
longer than 80-ft for most of the HF spectrum.
-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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RHF
> TailGator wrote:
> >
> > Agree wholeheartedly with the dipole comments - I live on the Gulf coast of
> > Florida, right on the water, and have an 80-ft longwire, end-fed, about 35
> > feet up and sloping down to a fence post. Coax to a Grove TUN-4 and an Icom
> > R75 and a Drake. Reception is fantastic! Can't go wrong with a long...wire,
> > that is:)
>
> What you have is a sloping inverted-L antenna. A real longwire is much
> longer than 80-ft for most of the HF spectrum.
TailGator & StarMan,
FWIW: More 'properly' called a "Random" Wire Antenna
- - - Vice a [Longwire] Antenna
IIRC: A 80 Foot single wire would be 'about' . . .
* Half Wave Length at 6 MHz
* * One Wave Length at 12.5 MHz
* * * Two Wave Lengths at 25 MHz
NOTE: Not enough information to determine if this would be a:
[ ] Simple Top End Feed Slopper
(Vice the Bottom End Feed Slopper)
- - -or- - -
[ ] Inverted "L" Sloper
(The so called "Lazy L" or "Tilted L" Antenna.)
iane ~ RHF
.
WShoots1
something like 500 feet.
Bill, K5BY
starman
> > longer than 80-ft for most of the HF spectrum.
>
> TailGator & StarMan,
>
> FWIW: More 'properly' called a "Random" Wire Antenna
> - - - Vice a [Longwire] Antenna
Are all inverted-L's, random wires?
CW
intended that. If you just threw out a piece of wire, that's random.news:3F52D88D...@tech.net...
RHF
= = = wrote in message news:<3F52D88D...@tech.net>...
> RHF wrote:
> >
> > starman <sta...@tech.net> wrote in message news:<3F4D8DF5...@tech.net>...
> > >
> > > What you have is a sloping inverted-L antenna. A real longwire is much
> > > longer than 80-ft for most of the HF spectrum.
> >
> > TailGator & StarMan,
> >
> > FWIW: More 'properly' called a "Random" Wire Antenna
> > - - - Vice a [Longwire] Antenna
>
> Are all inverted-L's, random wires?
StarMan,
In a word "NO" !
If, by 'design' for a specific band of frequencies an Inverted "L"
Antenna has the Horizontal Top Section equal to One Wavelength and a
Vertical End Section equal to One Half Wavelength; then it would be
considered a Longwire Antenna for that Band.
EXAMPLE: 25 Meter SW Band (11.6 - 12.1 MHz) Inverted "L" Antenna
- - - Horizontal Top Section = 85 Ft (One Wavelength)
- - - Vertical End Section = 42 Ft (Half Wavelength)
* * * NOTE: This same Inverted "L" Antenna would be useable on the 49
Meter SW Band (5.95 - 6.2 MHz)
- - - Horizontal Top Section = 85 Ft (Half Wavelength)
- - - Vertical End Section = 42 Ft (Quarter Wavelength)
FWIW: Most people think of the term "Longwire Antenna" as they apply
to the low frequencies especially the AM/MW/BCB where a One Wavelength
Antenna would be Bottom 540kHz = 1860Ft; Middle 1120kHz = 900Ft; Top
1700kHz = 590Ft. But, a Longwire Antenna is a Longwire Antenna when
its length is equal to One Wavelength (or more) at a given frequency.
It then follows that the same "Longwire Antenna" would be Two
Wavelengths, a Half Wavelength, and a Quarter Wavelength at other
frequencies. However, at all other frequencies this "Longwire
Antenna" is simply a 'random' wire antenna.
iane ~ RHF
Telamon
wrote:
> RHF wrote:
> >
> > starman <sta...@tech.net> wrote in message
> > news:<3F4D8DF5...@tech.net>...
> > >
> > > What you have is a sloping inverted-L antenna. A real longwire is much
> > > longer than 80-ft for most of the HF spectrum.
> >
> > TailGator & StarMan,
> >
> > FWIW: More 'properly' called a "Random" Wire Antenna
> > - - - Vice a [Longwire] Antenna
>
> Are all inverted-L's, random wires?
Depends on how you connect it to the radio. With just a single vertical
lead-in then yes but use a coax grounded in some way then no. Another
thing to consider is that the vertical portion should be a significant
portion of the antenna to qualify as an inverted L. An antenna that is
15 feet high and 150 feet long the vertical portion is only 10% of the
total pickup area. I would consider that to be a horizontal random/long
wire.
--
Telamon
Ventura, California
CW
"RHF" <rhf-...@pacbell.net> wrote in message
news:e5e13af8.03090...@posting.google.com...
> StarMan,
>
> In a word "NO" !
>
> If, by 'design' for a specific band of frequencies an Inverted "L"
> Antenna has the Horizontal Top Section equal to One Wavelength and a
> Vertical End Section equal to One Half Wavelength; then it would be
> considered a Longwire Antenna for that Band.
> >
> >
CW
"Telamon" <telamon_s...@pacbell.net.is.invalid> wrote in message
news:telamon_spamshield-4...@news.sf.sbcglobal.net...
>
> Depends on how you connect it to the radio. With just a single vertical
> lead-in then yes but use a coax grounded in some way then no.
Feedline type has nothing to do with it. The classic inverted L was
connected with a single wire feedline. Coax feed is often used now but not
always. I, and many others, have run inverted Ls (transmitting) right off
the back of the radio.
> Another
> thing to consider is that the vertical portion should be a significant
> portion of the antenna to qualify as an inverted L. An antenna that is
> 15 feet high and 150 feet long the vertical portion is only 10% of the
> total pickup area. I would consider that to be a horizontal random/long
> wire.
There is a bit of truth to that. It is generally excepted that an inverted
L is most efficient when the verticle portion is as long as possible.
> --
> Telamon
> Ventura, California
CW
starman
I doubt if most people try to make their inverted-L resonant for a
particular frequency. However in many cases it does turn out to be
resonant (like a longwire) at some frequency, particularly at the high
end of the HF spectrum where it's one or more wavelengths long.
CW
cut to a resonant length. It is still quite popular particularly on the
lower frequencies. As a receiving antenna, few people try for resonance as
they are usually after broad band operation.news:3F543939...@tech.net...
Telamon
"CW" <clinton...@comcast.net> wrote:
> "Telamon" <telamon_s...@pacbell.net.is.invalid> wrote in
> message
> news:telamon_spamshield-4...@news.sf.sbcglobal.net...
> >
> > Depends on how you connect it to the radio. With just a single
> > vertical lead-in then yes but use a coax grounded in some way then
> > no.
>
> Feedline type has nothing to do with it. The classic inverted L was
> connected with a single wire feedline. Coax feed is often used now
> but not always. I, and many others, have run inverted Ls
> (transmitting) right off the back of the radio.
If a coax cable is the vertical section then there is no vertical part
to the antenna so the answer is no. If it is a single wire then the
lead-in is part of the antenna and will radiate similar to the
horizontal section.
> > Another thing to consider is that the vertical portion should be a
> > significant portion of the antenna to qualify as an inverted L. An
> > antenna that is 15 feet high and 150 feet long the vertical portion
> > is only 10% of the total pickup area. I would consider that to be a
> > horizontal random/long wire.
>
> There is a bit of truth to that. It is generally excepted that an
> inverted L is most efficient when the verticle portion is as long as
> possible.
I went looking for a definition and could not find one specifically. The
closest I could find resembled a Marconi type where the vertical and
horizontal sections were 1/8 wavelength each or 50%.
--
Telamon
Ventura, California
RHF
"the vertical portion should be a significant portion of the antenna
to qualify as an inverted L. An antenna"
TRUE - Look at the Letter "L" and you will see that an Inverted "L"
Antenna will have an END (Vertical) to TOP (Horizontal) 'aspect ratio'
between 1:1.5 (2:3) and 1:2; but beyond 1:4 it is really not an "L"
any more.
iane ~ RHF
.
.
= = = Telamon <telamon_s...@pacbell.net.is.invalid>
= = = wrote in message news:<telamon_spamshield-4...@news.sf.sbcglobal.net>...
RHF
= = = wrote in message news:<20030828235319...@mb-m11.aol.com>...
> "Random wire" is the correct term, unless it is, as noted, a truly long wire,
> something like 500 feet.
>
> Bill, K5BY
Bill - K5BY,
I Will Repeat Myself: Most people think of the term "Longwire
Antenna" as they apply to the low frequencies especially the AM/MW/BCB
where a One Wavelength Antenna would be Bottom 540kHz = 1860Ft; Middle
1120kHz = 900Ft;
Top 1700kHz = 590Ft.
BUT, by 'definition' a "Longwire Antenna" is a "Longwire Antenna" when
its length is equal to One Wavelength (or more) at a given frequency.
EXAMPLES: One Wavelength "Longwire" Antennas for the following SW
Bands
49M Band = 165Ft
41M Band = 137Ft
31M Band = 104Ft
25M Band = 85Ft
22M Band = 73Ft
19M Band = 65Ft
16M Band = 57Ft
- - - All of which are less than 500Ft or more.
It then follows that the same "Longwire Antenna" would be Two
Wavelengths, a Half Wavelength, and a Quarter Wavelength at other
frequencies.
However, at all other frequencies this "Longwire Antenna" is simply a
'random' wire antenna.
RHF
By lack of 'design' most Inverted "L" Antennas are made to . . .
- - - FIT the "Available Space"
? How High I Can Get the Wire Up ?
- - - - - - - - & - - - - - - - -
? How Long Can I Stretch the Wire Out ?
[So that is the antenna that is built]
An antenna that is 'made' to the Physical (Space) Limitations . . .
- - - Not an Antenna that is 'built' to the Electrical Requirements.
So through lack of 'design' these antennas are "Random Wires" met to
be used across the MW/SW Bands from 500kHz and 30MHz.
Having said this any piece of wire will be one wavelength at a some
given frequency and thus resonate at that frequency; thereby being a
"Longwire" Antenna for that one frequency.
iane ~ RHF
.
.
= = = "CW" <clinton...@comcast.net>
= = = wrote in message news:<TnT4b.246013$cF.78375@rwcrnsc53>...
RHF
YES, for a Classic "Longwire" Antenna, sizing is about the 'length' of
the Horizontal Wire.
BUT - The subject here is an Inverted "L" Antenna that would NOT be a
'random wire antenna'.
So the first consideration would be maintaining the Shape (aspect
radio) of the Inverted "L" Antenna.
Then the second consideration would be sizing the Inverted "L" Antenna
to be resonte at a given frequency (SW Band) for some one who had a
specific interest in that band.
One simple method would have been to suggest making the total length
of the Inverted "L" Antenna one wavelength for that band:
EXAMPLES: Total Length equals Vertical plus Horizonal Sections
49M Band = 165Ft Total
41M Band = 137Ft Total
31M Band = 104Ft Total
25M Band = 85Ft Total
22M Band = 73Ft Total
19M Band = 65Ft Total
16M Band = 57Ft Total
A better method would have been to suggest making the TOP Section of
the Inverted "L" Antenna One Wavelength and the END Section of the
Inverted "L" Antenna a Half Wavelength. Thereby maintaining the
Inverted "L" Antennas Aspect Radio of 2H:1V (Shape Factor).
NOTE: This better method is what I choose to describe in my prior
post.
EXAMPLES: "L" Section Lengths for Horizontal and Vertical.
49M Band = 165Ft Horizontal & 83Ft Vertical
41M Band = 137Ft Horizontal & 68Ft Vertical
31M Band = 104Ft Horizontal & 52Ft Vertical
25M Band = 85Ft Horizontal & 42Ft Vertical
22M Band = 73Ft Horizontal & 37Ft Vertical
19M Band = 65Ft Horizontal & 33Ft Vertical
16M Band = 57Ft Horizontal & 28Ft Vertical
iane ~ RHF
.
.
= = = "CW" <clinton...@comcast.net>
= = = wrote in message news:<ngV4b.150729$2x.4...@rwcrnsc52.ops.asp.att.net>...
starman
>
> Telamon,
>
> "the vertical portion should be a significant portion of the antenna
> to qualify as an inverted L. An antenna"
>
> TRUE - Look at the Letter "L" and you will see that an Inverted "L"
> Antenna will have an END (Vertical) to TOP (Horizontal) 'aspect ratio'
> between 1:1.5 (2:3) and 1:2; but beyond 1:4 it is really not an "L"
> any more.
The vertical section of the inverted-L is also important for receiving
certain kinds of signals (propagation related) that the horizontal
section is less sensitive to.
RHF
That is True.
IIRC: Many of the 'original' HAM Transmitting Inverted "L" Antennas
were Quarter Wavelength Antennas with 1/8 Vertical and 1/8 Horizontal
for dual polarization of the signal in-theory (near and far
propagation ?).
The 'evolution' of the Inverted "L" Antenna application to an
'available space concept' for a SWL Receiving "Only" Antenna;
generally has the Top/Horizontal Section about twice as long as the
End/Vertical Section.
NOTE: Reversing the "L" and having the End Section feed point at the
far end of the antenna with a buried Coax Cable running directly under
it (acting as a Counterpoise) makes for a better (lower noise)
receiving antenna.
iane ~ RHF
.
.
= = = starman <sta...@tech.net>
= = = wrote in message news:<3F557A51...@tech.net>...
Robert F Wieland
Telamon <telamon_s...@pacbell.net.is.invalid> wrote:
>In article <3F52D88D...@tech.net>, starman <sta...@tech.net>
>>
>> Are all inverted-L's, random wires?
>
> Depends on how you connect it to the radio. With just a single vertical
> lead-in then yes but use a coax grounded in some way then no. Another
> thing to consider is that the vertical portion should be a significant
> portion of the antenna to qualify as an inverted L. An antenna that is
> 15 feet high and 150 feet long the vertical portion is only 10% of the
> total pickup area. I would consider that to be a horizontal random/long
> wire.
>
>--
>Telamon
>Ventura, California
Nothing about antenna theory seems to ever be simple. The antenna you
describe, above about 15MHz, will have a horizontal pattern quite
different from a 150 foot horizontal wire. The horizontal wire will have
a horizontal pattern like the petals of a warped daisy flower, with many
lobes separated by deep nulls, some more than 40dB 'deep'. That
vertical section of the above-described inverted-L will do quite a bit to
fill in those nulls.
Also, the inverted-L is simple to ground. Electromagnetic theory does not
require such a ground, but your friendly local Electrical Code does.
Not saying you're wrong, Telamon; below 10 MHz, you're basically right.
Just saying that we SW & scanner types work with wavelengths from about
one mile down to about a foot, and it's hard to find rules or principles
that apply uniformly across the whole range.
--
R F Wieland Newark, DE 19711-5323 USA 39.68N 75.74W
Icom R75 Heathkit GR-81 Inverted-L in the attic
Reply to wieland at me dot udel dot edu
RHF
What would be your evaluation of these three
SWL (Receive Only) Inverted "L" Antennas:
* 49M Band Half Wavelength Inverted "L" Antenna
Vertical 27.6 Feet and Horizontal 55.1 Feet with a Total of 82.7 Feet
- - - V = 1/6WL & H = 1/3WL
* 49M Band Three Quarter (3/4) Wavelength Inverted "L" Antenna
Vertical 41.4 Feet and Horizontal 82.7 Feet with a Total of 124.1 Feet
- - - V = 1/4WL & H = 1/2WL
* 49M Band Full Wavelength Inverted "L" Antenna
Vertical 55.1 Feet and Horizontal 110.3 Feet with a Total of 165.4 Feet
- - - V = 1/3WL & H = 2/3WL
iwtk ~ RHF
.
.
= = = wie...@copland.udel.edu
= = = (Robert F Wieland) wrote in message news:<bj8cno$g9f$1...@copland.udel.edu>...