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#11
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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 |
#12
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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! =----- |
#13
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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! =----- |
#14
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"Random wire" is the correct term, unless it is, as noted, a truly long wire,
something like 500 feet. Bill, K5BY |
#15
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= = = 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! =----- |
#16
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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 |
#17
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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! =----- |
#18
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"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 |
#19
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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. |
#20
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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! =----- |
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