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Shortwave Antenna
Would an antenna like the one in the link be any good? I am looking for a
decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...Fid=278%2D1374 Any advice would be helpful. thanks, Paul |
Radio Shack offers a very useful antenna kit for shortwave listeners.
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. |
radio Shack, hardware store etc s. Other days recently, reception has not
been so good lately. |
Hi Paul:
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/ http://www.hard-core-dx.com/index.php?topic=antennas Dan In article , "Paul" writes: Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...ategory%5Fname =CTLG%5F008%5F009%5F002%5F000&product%5Fid=278%2D1 374 Any advice would be helpful. thanks, Paul |
Paul
- Better link for shortwave antenna info...... http://www.hard-core-dx.com/nordicdx/antenna/wire/ In article , "Paul" writes: Mon, 25 Aug 2003 16:54:13 -0500 Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...ategory%5Fname =CTLG%5F008%5F009%5F002%5F000&product%5Fid=278%2D1 374 Any advice would be helpful. thanks, Paul |
On Mon, 25 Aug 2003 22:14:42 GMT, "Warpcore" wrote:
Radio Shack offers a very useful antenna kit for shortwave listeners. 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. 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 ======================= |
Warpcore wrote: If it slants down, that is beneficial for reducing noise. Can you explain why this is? Dale W4OP |
"Paul" wrote in
: Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...&category%5Fna me=CTLG%5F008%5F009%5F002%5F000&product%5Fid=278%2 D1374 Any advice would be helpful. thanks, Paul 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 |
Well I can imagine after all that! Well that seems to be the majority, the
dipole "Kruppt" wrote in message 01... "Paul" wrote in : Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...&category%5Fna me=CTLG%5F008%5F009%5F002%5F000&product%5Fid=278%2 D1374 Any advice would be helpful. thanks, Paul 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,
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&i...=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...enna/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...nna/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" = = = wrote in message ... Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...Fid=278%2D1374 Any advice would be helpful. thanks, Paul |
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:) John KF4ANC "Paul" wrote in message ... Would an antenna like the one in the link be any good? I am looking for a decent shortwave antenna. I mainly listen to 11.175 USB and 5-9mhz USB. http://www.radioshack.com/product.as...gory%5Fname=CT LG%5F008%5F009%5F002%5F000&product%5Fid=278%2D1374 Any advice would be helpful. thanks, Paul |
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. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
starman wrote in message ...
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 .. .. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Random wire" is the correct term, unless it is, as noted, a truly long wire,
something like 500 feet. Bill, K5BY |
= = = starman
= = = wrote in message ... RHF wrote: starman wrote in message ... 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 -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
In article , starman
wrote: RHF wrote: starman wrote in message ... 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 |
Not at all. In any case, he asked about an inverted L.
"RHF" wrote in message om... 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. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Telamon" wrote in message ... 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 |
Better look up long wire. Verticle length has nothing to do with it.
"RHF" wrote in message om... 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. |
RHF wrote:
= = = starman = = = wrote in message ... RHF wrote: starman wrote in message ... 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. 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. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
The inverted L was originally conceived as a transmitting antenna and was
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. "starman" wrote in message ... 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. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
In article ,
"CW" wrote: "Telamon" wrote in message ... 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 |
|
Hello CW,
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" = = = wrote in message . net... Better look up long wire. Verticle length has nothing to do with it. "RHF" wrote in message om... 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. |
StarMan,
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 = = = wrote in message ... RHF wrote: 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. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
In article ,
Telamon wrote: In article , starman [snip] 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 |
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