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Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On 7 Mar 2006 23:50:11 -0800, "RHF"
wrote: For One and All, QUESTION - Shortwave Listening (SWL) Antenna Tuners - - - Do You Have An Opinion ? - - - Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening http://www.nyx.net/~dgrunber/tuner.ssi - - - by - - - Daniel A. Grunberg The same argument could be used to say, "Why 9-to-1 Baluns Aren't Necessarily Useful for Shortwave Listening." Bob k5qwg |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Wed, 08 Mar 2006 14:58:45 GMT, Bob Miller
wrote: On 7 Mar 2006 23:50:11 -0800, "RHF" wrote: For One and All, QUESTION - Shortwave Listening (SWL) Antenna Tuners - - - Do You Have An Opinion ? - - - Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening http://www.nyx.net/~dgrunber/tuner.ssi - - - by - - - Daniel A. Grunberg The same argument could be used to say, "Why 9-to-1 Baluns Aren't Necessarily Useful for Shortwave Listening." Bob k5qwg If one is a true RF professional the idea of putting a Hi Z generator into a Low Z load is too much. The 9:1 autotransormer also puts every part of the antenna at DC ground, thus protecting the radio's input. Plus, it's a very elegant way to connect the wire to the shielded cable. |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Wed, 08 Mar 2006 15:17:18 GMT, David wrote:
On Wed, 08 Mar 2006 14:58:45 GMT, Bob Miller wrote: On 7 Mar 2006 23:50:11 -0800, "RHF" wrote: For One and All, QUESTION - Shortwave Listening (SWL) Antenna Tuners - - - Do You Have An Opinion ? - - - Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening http://www.nyx.net/~dgrunber/tuner.ssi - - - by - - - Daniel A. Grunberg The same argument could be used to say, "Why 9-to-1 Baluns Aren't Necessarily Useful for Shortwave Listening." Bob k5qwg If one is a true RF professional the idea of putting a Hi Z generator into a Low Z load is too much. The 9:1 autotransormer also puts every part of the antenna at DC ground, thus protecting the radio's input. Plus, it's a very elegant way to connect the wire to the shielded cable. Still, you have that wonderfully sensitive receiver, and your balun hasn't changed the signal to noise ratio; it's only made everthing louder. Same argument he's using against antenna tuners :-) bob k5qwg |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Wed, 08 Mar 2006 17:05:33 GMT, Bob Miller
wrote: Still, you have that wonderfully sensitive receiver, and your balun hasn't changed the signal to noise ratio; it's only made everthing louder. Same argument he's using against antenna tuners :-) bob k5qwg It does help signal:noise. It keeps the antenna away from the house. |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Wed, 08 Mar 2006 18:40:32 GMT, David wrote:
On Wed, 08 Mar 2006 17:05:33 GMT, Bob Miller wrote: Still, you have that wonderfully sensitive receiver, and your balun hasn't changed the signal to noise ratio; it's only made everthing louder. Same argument he's using against antenna tuners :-) bob k5qwg It does help signal:noise. It keeps the antenna away from the house. And the rest of the noise? Powerlines, atmospheric noise, heterodynes, etcetera? And do you really think coax keeps manmade noise out? bob k5qwg |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Wed, 08 Mar 2006 20:27:57 GMT, Bob Miller
wrote: On Wed, 08 Mar 2006 18:40:32 GMT, David wrote: On Wed, 08 Mar 2006 17:05:33 GMT, Bob Miller wrote: Still, you have that wonderfully sensitive receiver, and your balun hasn't changed the signal to noise ratio; it's only made everthing louder. Same argument he's using against antenna tuners :-) bob k5qwg It does help signal:noise. It keeps the antenna away from the house. And the rest of the noise? Powerlines, atmospheric noise, heterodynes, etcetera? And do you really think coax keeps manmade noise out? bob k5qwg It keeps the noise I make out of my radio. |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
Telamon wrote in
: In article . com, wrote: If one is a true RF professional the idea of putting a Hi Z generator into a Low Z load is too much. LOL...A true RF pro probably wouldn't use a random wire in the first place.. :/ They work well in a low local noise location. A random or long wire could be a good reference antenna against a new design. And a wire is also quick & Cheap, when you need something in a hurry. |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
They work well in a low local noise location.
As will nearly anything. A random or long wire could be a good reference antenna against a new design. To me, a random wire would be a poor reference antenna. To me, there are basically two reference antennas. The horizontal dipole, which would be the reference for horizontal antennas, and the 1/4 monopole, which would be a reference to compare against vertical antennas. For elevated verticals, I use the 1/4 wave ground plane as the reference antenna. A random wire is much too random. The antennas I use as benchmarks all have well known and repeatable performance. All my horizontal wire antennas are compared to the 1/2 wave dipole. BTW, not many win either, unless they are gain antennas. As far as efficiency on a certain band, it's hard to beat a coax fed dipole. And thusly, it's my usual "benchmark" antenna. MK |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
For One and All,
THE PROFESSIONAL {AMATEUR} VIEW POINT - - - HAMMING IT UP ! - - - The 1/2 Wave Length Dipole and the 1/4 Wave Length Vertical are both good Technical {Reference} Antennas for the "Specific Frequency" related to their Measured Wave Lengths. For Amateur {Ham} Radio use where you are Operating in a Certain Amateur Band and on a Single Selected Frequency; they are excellent Receive and Transmit Antennas. SHORWAVE LISTENING (SWL) - HEY IT'S JUST A HOBBY [ KEEPING IT SIMPLE AND PRACTICAL ] {KISAP} The Random Wire Antenna that is generally good on All Frequencies across the Shortwave Bands from 1.8 MHz to 30 MHz is the most commonly used Antenna for Shortwave Listening (SWL) and thus is the Practical {Reference} Antenna for the Shortwave Listener (SWL). It is simply A-Common-Point-of-Reference for All Shortwave Listeners (SWLs) to 'compare' the relative perfromance of their respective Shortwave Listening (SWL) Antennas. The Random Wire Antenna, while not very good on any Specific Frequency is simply so-so-good across All Shortwave Frequencies. To some extent the qualities that make an 'un-tuned' Random Wire a poor Amateur Antenna; are the same qualities that make it a very good Shortwave Listening (SWL) Antenna. The modern solid-state General Coverage 1.8 MHz to 30 MHz Shortwave Receiver has enough Gain and sufficient Dynamic Range to make full use of the Signal Levels that can be producted by a Random Wire Antenna that is 35 Feet to 105 Feet long. For most Shortwave Listeners (SWLs) what more do they need other than Lower Noise and Better Signal Quality relative to Noise. {Improved Signal-to-Noise S/N Ratio}. The-Bottom-Line : The Random Wire Antenna is : + Simple + Practical + More Than "Good Enough" For the vast majority of the Shortwave Listener's (SWLs) Shortwave Radio Listening Needs [.] THE NEXT STEP - LOW NOISE INVERTED "L" {RANDOM WIRE} ANTENNA Starting with the Random Wire Antenna and incorporating a few improvements can result in an Shortwave Listening (SWL) Antenna that has for it's size and placement a better Signal-to-Noise S/N Ratio then a plain Random Wire {so-called Longwire} Antenna THREE-TO-READ BY JOHN DOTY : * The Inverted "L" Antenna 'Shape' lends itself to the Design Concepts of a "Low Noise Antenna" that has been popularized by John Doty; consisting of: Antenna Element; Matching Transformer; Grounding Point; Coax Cable Feed-in-Line; and Radio/Receiver. DOTY= http://www.anarc.org/naswa/badx/ante...e_antenna.html http://groups.yahoo.com/group/Shortw...enna/message/2 http://groups.yahoo.com/group/Shortw...na/message/374 - Two Reasons to use a Balun (Matching Transformer) with a Receive Only Antenna. DOTY= http://www.anarc.org/naswa/badx/ante..._longwire.html http://groups.yahoo.com/group/Shortw...na/message/150 - Magnetic Longwire Balun (MLB) - Build Your Own "DIY" http://groups.yahoo.com/group/Shortw...na/message/177 http://groups.yahoo.com/group/Shortw...na/message/466 http://groups.yahoo.com/group/Shortw...na/message/467 - Balun Reading List ( Long ) http://groups.yahoo.com/group/Shortw...na/message/337 - The "Grounding-Point" = Ground Rods and Ground Wires ETC. DOTY= http://www.anarc.org/naswa/badx/antennas/grounding.html http://groups.yahoo.com/group/Shortw...na/message/425 http://www.hard-core-dx.com/nordicdx/antenna/ground/ http://groups.yahoo.com/group/Shortw...na/message/470 http://groups.yahoo.com/group/Shortw...na/message/539 LIST OF MORE TO READ - Low-Noise Invered "L" Antenna * How does the "Doty" Inverted-L Antenna do . . . http://groups.google.com/group/rec.r...ff7ab457d5966c http://groups.google.com/group/rec.r...aaa91efcba72d6 http://groups.google.com/group/rec.r...1f2641323eed34 http://groups.google.com/group/rec.r...a2a935f52a5d65 * Question is 'it' a Longwire {Random Wire} Antenna -or- Inverted "L" Antenna ? http://groups.google.com/group/rec.r...364956151adbba http://groups.google.com/group/rec.r...f4e4ded6f94686 http://groups.google.com/group/rec.r...a571f3bebdca61 * Questions on Inverted "L" Antenna http://groups.google.com/group/rec.r...b3ddbed819958d http://groups.google.com/group/rec.r...f7b5506cc942e2 http://groups.google.com/group/rec.r...90a154db93a89a http://groups.google.com/group/rec.r...4b09ea224f4434 * Basic Antenna Question - - - Noise Reducing Antennas The SWL Version of the Inverted "L" Antenna works well as an Omni-Directional Antenna. http://groups.google.com/group/rec.r...6c390272c6c91f http://groups.google.com/group/rec.r...463ad863e5b075 http://groups.google.com/group/rec.r...ffeaab835e3bb6 * WHY - The simple Random Wire Antenna is better than the Dipole Antenna for the Shortwave Listener (SWL) http://groups.google.com/group/rec.r...023dcbd76abc37 http://groups.google.com/group/rec.r...ecfc2f91fe5c7e http://groups.google.com/group/rec.r...d43c05075de087 http://groups.google.com/group/rec.r...ed7dc5f3aadadc http://groups.google.com/group/rec.r...38331627ba89a1 * Random Wire Antenna Question . . . http://groups.google.com/group/rec.r...2aaad971aa2c2f http://groups.google.com/group/rec.r...56237ce6553389 http://groups.google.com/group/rec.r...68df4a9df55dae http://groups.google.com/group/rec.r...3fe02cad4e5650 * Low Noise Shortwave Listener's (SWL) Antenna - by Design http://groups.google.com/group/rec.r...ab857189fec531 http://groups.google.com/group/rec.r...26baf640c5d346 http://groups.google.com/group/rec.r...be7387aae66292 http://groups.google.com/group/rec.r...b0ba01c418c6c9 http://groups.google.com/group/rec.r...57f23580332f73 http://groups.google.com/group/rec.r...07cc179fcc3dbd http://groups.google.com/group/rec.r...e1f930c8d189db * Consider Buying or Building a better Shortwave Listener's (SWL) Antenna. http://groups.google.com/group/rec.r...2ff595de9fea91 http://groups.google.com/group/rec.r...f41e85486b0ed9 http://groups.google.com/group/rec.r...11c0ac4f084b87 http://groups.google.com/group/rec.r...ffeaab835e3bb6 hope this helps - iane ~ RHF . . Tous Sont Bienvenus ! - - - Groupe par Radio d'auditeur d'onde courte pour des Antennes de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Alle Sind Willkommen ! - - - Shortwave Radiozuhörer Gruppe für SWL Antennen http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Tutti Sono Benvenuti ! - - - Gruppo Radiofonico dell'ascoltatore di onda corta per le Antenne di SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Todos São Bem-vindos ! - - - Grupo de Rádio do ouvinte do Shortwave para Antenas de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . Все *адушны ! - - - Группа оператора на приеме коротковолнового диапазона Radio для Aнтенн SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . ¡Todos Son Agradables! - - - Grupo de Radio del oyente de la onda corta para las Antenas de SWL http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . = = = = = Translation = = = = = All are Welcome - - - To Join the Shortwave Listeners (SWL) Antenna Group on YAHOO ! http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ . . .. . |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
You are not making logical sense. The random wire non-resonant common
mode antenna is a good reference antenna precisely because it has little theoretical gain and it will work anywhere. So the same can be said for a 1/2 wave dipole. The gain of a length of wire will not vary much depending on how it's fed. Only the length really matters. Of course, different methods of feeding vary as far as system efficiency. In the case of 1/2 wave or smaller wires, the efficiency of the feed system is about the only thing that matters much among the various versions of such. You compare it against a dipole and the dipole should show gain over it as should any other antenna type made to be resonant at some frequency. How you fiqure? If the random wire were longer than the 1/2 WL dipole, it could actually have more gain in a certain direction. The reason a dipole is the common benchmark for horizontal wires is because it's a well known measured quanity. Exactly what you want as a "benchmark", or reference antenna. Look at most any antenna ad's for yagi's. If you can find one that is measured against a random wire, I'll send you $20. Most all will be measured against a 1/2 wave dipole at the same height, or instead be listed as dbi, which is a theoretical value. The only difference between dbd and dbi is about 2.1 db. You are just shifting your reference. Stop thinking like an amateur, this is a SW listening news group. What does that have to do with anything? I place no distinction between an antenna used for transmit, and one receive. They both obey the same laws. I use the same types of antennas for both jobs. The better an antenna is at transmitting , in general ditto for receive. The properties of an antenna between transmit, and receive are reciprical. IE: if an antenna has gain in a certain direction, this applies equally transmit, or receive. I will always use the best antenna for the job I can put up. And that is rarely ever a random wire. Random wires are too micky mouse for my blood. But you can consider that a personal problem. :/ A random wire is the basic antenna here. Sure, it may be for some, but I'm sure not all are content to stay with one antenna their whole life. I'm just as much as SWL as you are, and my "basic" antenna is a 1/2 wave dipole. I've been SWLing since 1964, when I got my first radio at the age of 8. A good bit longer than I've been a ham. I didn't get into ham radio until the 8th grade. Didn't get legal until 77. When did you start SWLing? If it's longer than 42 years, I'll give you a free cookie. If you want technical antenna theory then yeah a dipole is a basic reference radiator most transmit antennas. Whether it's for transmit or not is not really relevant. What other kind of antenna theory is there? Do they also have "sears" antenna theory, "geico" antenna theory, "dimbulb" antenna theory, etc? I thought there was just one version... Heck, the other guy was the one that brought up what "pro's" would use or do. Pro's don't measure antennas against random wires. And I doubt most would use one if they could use something better. I don't use random wires, and I'm not even a pro. :/ Are you suggesting I would be a better SWLer if I changed to random wires? That'll be the day... :/ LOL... MK -- |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
Hey, you asked for opinions in your first post
of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On 11 Mar 2006 23:12:08 -0800, "RHF"
wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg For One and All, THE PROFESSIONAL {AMATEUR} VIEW POINT - - - HAMMING IT UP ! - - - Amateurs are not professionals... excerpted... excerpted... |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 14:26:15 GMT, Bob Miller
wrote: On 11 Mar 2006 23:12:08 -0800, "RHF" wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg ''Random length dipole'' makes little sense. |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 15:33:26 GMT, David wrote:
On Sun, 12 Mar 2006 14:26:15 GMT, Bob Miller wrote: On 11 Mar 2006 23:12:08 -0800, "RHF" wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg ''Random length dipole'' makes little sense. aka 'Doublet' where you have two equal lengths of wire that are not cut to any specific frequency, rather they are cut to fit the maximum dimension you have available. Doublets are typically fed with twinlead and a tuner is used. |
The Next Step - The Low Noise Inverted"L" {Random Wire} Antenn...
I am thinking I might string a sloper antenna wire out in my back
yard.If I think an antenna tuner might be usefull for me,I will drive on over to MFG Enterprises and let them folks suggest something for me.Noo to much a drive for me to make,we are in the same State. cuhulin,the Mississippi |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenn...
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 07:42:11 -0800, wrote:
On Sun, 12 Mar 2006 15:33:26 GMT, David wrote: On Sun, 12 Mar 2006 14:26:15 GMT, Bob Miller wrote: On 11 Mar 2006 23:12:08 -0800, "RHF" wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg ''Random length dipole'' makes little sense. aka 'Doublet' where you have two equal lengths of wire that are not cut to any specific frequency, rather they are cut to fit the maximum dimension you have available. Doublets are typically fed with twinlead and a tuner is used. Dipole Slide Show: http://www.ycars.org/presentations/b...20part%20i.ppt |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 17:26:33 GMT, Bob Miller
wrote: On Sun, 12 Mar 2006 07:42:11 -0800, wrote: On Sun, 12 Mar 2006 15:33:26 GMT, David wrote: On Sun, 12 Mar 2006 14:26:15 GMT, Bob Miller wrote: On 11 Mar 2006 23:12:08 -0800, "RHF" wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg ''Random length dipole'' makes little sense. aka 'Doublet' where you have two equal lengths of wire that are not cut to any specific frequency, rather they are cut to fit the maximum dimension you have available. Doublets are typically fed with twinlead and a tuner is used. An alternative would be a non-random length dipole resonant on several swl bands without the need for an antenna tuner. See... http://www.universal-radio.com/catalog/sw_ant/3377.html I used to have the sloper version of the above. Worked great. bob k5qwg http://www.hamuniverse.com/multidipole.html |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 07:42:11 -0800, wrote:
On Sun, 12 Mar 2006 15:33:26 GMT, David wrote: On Sun, 12 Mar 2006 14:26:15 GMT, Bob Miller wrote: On 11 Mar 2006 23:12:08 -0800, "RHF" wrote: A random length dipole will work as well as any random length "wire." With or without an antenna tuner. And be easier to feed. Bob k5qwg ''Random length dipole'' makes little sense. aka 'Doublet' where you have two equal lengths of wire that are not cut to any specific frequency, rather they are cut to fit the maximum dimension you have available. Doublets are typically fed with twinlead and a tuner is used. http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=7499 |
The Next Step - The Low Noise Inverted"L" {Random Wire} Antenn...
www.google.com MP3 Music Poland
Allyey wetahhhh,,,, shock me Alliwetahhhhh,,,,,,,, cuhulin (Polish music jazz) |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenn...
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
In article ,
wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. -- Telamon Ventura, California |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 22:28:19 GMT, Telamon
wrote: In article , wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. Telamon, Thanks for the friendly answer - however, I was aware of what you mention. My earlier response was just a case of me being flippant in my response to MK. Howard |
Why Antenna Tuners Aren't Necessarily Useful for Shortwave Listening - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
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The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
In article ,
wrote: On Sun, 12 Mar 2006 22:28:19 GMT, Telamon wrote: In article , wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. Telamon, Thanks for the friendly answer - however, I was aware of what you mention. My earlier response was just a case of me being flippant in my response to MK. When I post whether a new thread or in this case a reply I try to be informative as this is not like email where a reply would go directly to you. Hopefully other people reading the thread get a better idea of what will work better for them. Besides there is no way for me to know what you know or what experience you have except for what you explicitly write and I have to guess the rest. A level of knowledge a person has is an interesting thing in itself. Some people are aware of the reciprocity concept and leave it at that but you can always look at things in a deeper way that modify or even appear to reverse a rule. -- Telamon Ventura, California |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Sun, 12 Mar 2006 22:28:19 GMT, Telamon
wrote: In article , wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." Most transmitting antennas use wire about the same size as what's found in receiving-only antennas, 14 or 16 guage, maybe 12 guage for full legal power. 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. I seriously doubt you could hear the difference between a full size antenna at frequency, and one slightly shorter for space considerations. bob k5qwg |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
In article ,
Bob Miller wrote: On Sun, 12 Mar 2006 22:28:19 GMT, Telamon wrote: In article , wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." Most transmitting antennas use wire about the same size as what's found in receiving-only antennas, 14 or 16 guage, maybe 12 guage for full legal power. Ever calculate antenna resistance at HF for those gauges? What is the expected loss for some band you worked on? What is legal power for hams on HF? 1500 watts? And is that continuous power or PEP? 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. I seriously doubt you could hear the difference between a full size antenna at frequency, and one slightly shorter for space considerations. On receive the antenna efficiency is related to is size by means of radiation resistance. Antenna efficiency is directly dependent on the combination of radiation and antenna element resistance (DC+AC). This affects the received signal power just like it does for transmit but like I said on transmit you can use materials with higher dielectric constants and reactive components to launch an EM wave efficiently. However, on receive you can't affect the environment around the antenna in the same fashion as the antenna itself therefor what I stated stands unless you can refute it. The key here in the non-reciprocity of antenna performance is the fact that "you can't affect the environment around the antenna in the same fashion as the antenna itself." The environment around the antenna has an impedance value not affected by the antenna but antenna size directly correlates to radiation resistance. Think about it. If you were right then everyone would be using a whip antenna. Why bother to build full size antennas? -- Telamon Ventura, California |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
MK,
So you use the same Amateur Radio Antenna for the 160m and 80m Bands as you do for the 6m and 2m Bands. http://en.wikipedia.org/wiki/Amateur_radio 160-Meter Amateur Band = 1.815 to 1.89 MHz 80-Meter Amateur Band = 3.5 to 3.8 MHz 6-Meter Amateur Band = 50-54 MHz 2-Meter Amateur Band = 144-148 MHz MK # 1 - " An antenna is an antenna is an antenna. " But A Piece of Wire - Now That's Electrical ! :o) MK #2 - "Do you think when I switch from a SWL to a ham band, I need to switch antenna types? " MK - As an Amateur radio Opperator - If you were using a 20-Meter Dipole Antenna to Talk Coast-to-Coast http://www.chem.hawaii.edu/uham/20.html -or- a SkyWire {NVIS} Loop Antenna for your local-area "Net" Work http://groups.google.com/group/rec.r...c8553f4137bb58 http://groups.google.com/group/rec.r...1803362ae6952f http://groups.google.com/group/rec.r...73213a11be0b83 http://groups.google.com/group/rec.r...01f389f911c57d - - - Then just may be you would want to switch over to an 45 to 100 Foot Inverted "L" Shortwave Listener's (SWLs) Antenna to be able to Hear-Around-the-World from all directions with ease. * 45 Foot Shortwave Listener (SWL) Inverted "L" Antenna 15 Foot Vertical Up-Leg with a 30 Foot Horizontal Out-Arm * 100 Foot Shortwave Listener (SWL) Inverted "L" Antenna 25-33 Foot Vertical Up-Leg with a 67-75 Foot Horizontal Out-Arm http://groups.google.com/group/rec.r...92a8ef6391bce6 MORE "LN-ILA" READING = http://tinyurl.com/j9erj Note - LN-ILA = Low Noise Inverted "L" Antenna - a la John Doty just - keeping it simple and practical {KISAP} cause - iane ~ RHF |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
BM [K5QWG] - "Amateurs are not professionals..."
Most {The Majority} of Amateur {Ham} Radio Operators take "Their" Amateur Radio License as Personal Badge of Honor and it could be said that "They" view themselves as Hobbyist with a 'professional' Level of Technical Knowledge. - - - FWIW - IMHO - They Are Right [.] BM [K5QWG] - "And be easier to feed." Ah ! - Spoken like a True Amateur {Ham} Radio Operator. Speaking from the prospective of a Shortwave Listener (SWL) "The Wire(s)" connecting an Antenna (Wire Antenna Element) to the Radio {Receiver} are the Feed-in-Line : That which 'brings' the Radio Signal from the Antenna to the Radio. - - - Where as - The Amateur {Ham} Radio Operator 'thinks' of "The Wire(s)" connecting an Antenna to the Transmitter as the Antenna FEED : That which 'sends' the Radio Signal from the Transmitter to the Antenna. The Amateur {Ham} Radio Operator -vice- The Shortwave Listener (SWL) Two View Points : The Expertise of a Two-Way Communicator -vice- The Enjoyment of a Simple Radio Listener {Hobbyist} The-Bottom-Line - Shortwave {Radio} Listening (SWL) : it does not have to be technical to be enjoyable - iane ~ RHF FWIW - Just Keeping It Simple And Practical { KISAP :-} |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
On Mon, 13 Mar 2006 04:10:24 GMT, Telamon
wrote: In article , Bob Miller wrote: On Sun, 12 Mar 2006 22:28:19 GMT, Telamon wrote: In article , wrote: On 12 Mar 2006 01:08:39 -0800, wrote: Hey, you asked for opinions in your first post of the thread. If you don't like my opinions, thats too bad. An antenna is an antenna is an antenna. Do you think when I switch from a SWL to a ham band, I need to switch antenna types? LOL...You guys kill me.. MK Well how can your receiver work with an antenna made for transmit 8-} Basically (theoretically) an antenna made for transmit is just as suitable for receive. This is called reciprocity. This concept falls apart two ways in practicality: 1. The transmit situation has to handle power the receive situation does not so for transmit the antenna elements need to be "beefier." Most transmitting antennas use wire about the same size as what's found in receiving-only antennas, 14 or 16 guage, maybe 12 guage for full legal power. Ever calculate antenna resistance at HF for those gauges? What is the expected loss for some band you worked on? Well, I could have built my 80 meter dipole out of copper pipe, but the neighbors might have objected -- I used 18 guage stranded, which is fine for my 100 watts, and would probably handle legal power, too. For my 20 meter inverted L, I used #26 stranded. It's hooked to a mightly 3.5 watt qrp rig. What is legal power for hams on HF? 1500 watts? 1500, and I believe it's continuous, but you can check the FCC site if you wish. And is that continuous power or PEP? 2. A less than full size antenna made resonant may work very well for transmit but for receive not as well. Less than full size for receive lowers the antenna efficiency. I seriously doubt you could hear the difference between a full size antenna at frequency, and one slightly shorter for space considerations. On receive the antenna efficiency is related to is size by means of radiation resistance. Antenna efficiency is directly dependent on the combination of radiation and antenna element resistance (DC+AC). This affects the received signal power just like it does for transmit but like I said on transmit you can use materials with higher dielectric constants and reactive components to launch an EM wave efficiently. However, on receive you can't affect the environment around the antenna in the same fashion as the antenna itself therefor what I stated stands unless you can refute it. The key here in the non-reciprocity of antenna performance is the fact that "you can't affect the environment around the antenna in the same fashion as the antenna itself." The environment around the antenna has an impedance value not affected by the antenna but antenna size directly correlates to radiation resistance. Think about it. If you were right then everyone would be using a whip antenna. Why bother to build full size antennas? Well, they're more broad-banded, for one thing. Once again, less-than-half-wave antennas, properly tweaked, are as loud to my ears as half-wave antennas. I know I'm right because I'm talking about what I hear. As far as whip antennas go, actully, a lot of hams do pretty good on 75 meters with highly tweaked 6- or 8-foot whips on their cars. bob k5qwg |
The Next Step - The Low Noise Inverted "L" {Random Wire} Antenna - Question Shortwave Listening (SWL) Antenna Tuners - Do You Have An Opinion ?
MK,
Why Don't 'you' Try Answering the Questions Asked ? - - - vice - - - Going-Off and advoiding the facts and issues at hand ? MK - So 'you' are the type of Amateur Operator who uses one Antenna on All-Bands ? MK - Your 20-Meter Band 4-Element Yagi might be Great on the Amateur 20 Meter Band and be 'ok' on the 22 and 19 Meter Shortwave Bands - But honestly would 'you' use it on the 60-49-41-31 Meter Shortwave Bands ? ? ? For the Shortwave Listener an Inverted "L" Antenna that was 25 Feet High by 50 Feet Long would be a better General All-Band SWL Listening Antenna then your Yagi. Vertical-Up-Leg for 31-Meters = 1/4 WL @ 24.5 Feet Horizontal-Out-Arm for 60-Meters = 1/4 WL @ 47.7 Feet Total Length of the Wire Antenna Element 72.2 Feet = = = One Antenna : Built-It & Rig-It = Enjoy-It :o) [ An 'average' size SWL Antenna that can "Fit" InTo the Urban Backyard. ] For the Shortwave Listener wanting something a little Bigger then an Inverted "L" Antenna that was 32 Feet High by 71 Feet Long would be a little better General All-Band SWL Listening Antenna - If they had the Space and the Ability-to-Rig the Antenna Wire that High . Vertical-Up-Leg for 41-Meters = 1/4 WL @ 31.8 Feet Horizontal-Out-Arm for 90-Meters = 1/4 WL @ 70.9 Feet Total Length of the Wire Antenna Element 102.7 Feet = = = One Antenna : Built-It & Rig-It = Enjoy-It :o) [ A 'larger' size SWL Antenna that can "Fit" InTo the Urban Backyard. ] Alas, many Shortwave Listeners can only have an Inverted "L" Antenna that is a little smaller and 15 Feet High by 30 Feet Long would be the best that they could do for a General All-Band SWL Listening Antenna - Since that have very limited space and can only Rig oh-so-high. Vertical-Up-Leg for 19-Meters = 1/4 WL @ 15.1 Feet Horizontal-Out-Arm for 41-Meters = 1/4 WL @ 31.8 Feet Total Length of the Wire Antenna Element 46.9 Feet = = = One Antenna : Built-It & Rig-It = Enjoy-It :o) [ A 'small' size SWL Antenna that can "Fit" InTo the smaller Urban Backyard. ] Note - The Par EF-SWL Antenna lends itself to this 'small' Inverted "L" Antenna Rigging and it is only 45 Feet Long and includes the Wire Antenna Element and Matching Transformer - Just add Ground Rod plus Coax Cable and you are ready to Rig-It and Enjoy Listing to your Radios. http://www.universal-radio.com/catalog/sw_ant/2205.html * Par Electronics EF-SWL http://groups.google.com/group/rec.r...b0c1f933b5e495 http://groups.google.com/group/rec.r...85739bddf54cc3 http://groups.google.com/group/rec.r...2c697b586250c4 http://groups.google.com/group/rec.r...802953c2ef0642 http://groups.google.com/group/rec.r...68cb105b4a370b * ABOUT USING - The Par Electronics End-Fed Shortwave Listener {EF-SWL} Antenna http://groups.google.com/group/rec.r...f41e85486b0ed9 http://groups.google.com/group/rec.r...11c0ac4f084b87 http://groups.google.com/group/rec.r...d00e8131ee9876 http://groups.google.com/group/rec.r...a68a64cf6d8a00 http://groups.google.com/group/rec.r...157d690257b8ad * Consider Buying or Building a better Shortwave Listener's (SWL) Antenna. Lets Think : Out-of-the-Box {Ready-Made} Shortwave Listener (SWL) Antennas WHY - The simple Random Wire Antenna is better than the Dipole Antenna for the Shortwave Listener (SWL) http://groups.google.com/group/rec.r...2ff595de9fea91 http://groups.google.com/group/rec.r...1e9554b3d7d7ee http://groups.google.com/group/rec.r...905736ffa71e6e http://groups.google.com/group/rec.r...023dcbd76abc37 http://groups.google.com/group/rec.r...90a154db93a89a MK - Remember for the Shortwave Listener the SWL Antenna is just-a-means to being able to Listen to "Their" Radios and Enjoying the Listening Experience. mk - enjoy being a ham :o) -and- i will continue to enjoy . . . just being a shortwave listener (swl) - iane ~ RHF |
MK - For the Shortwave Listener (SWL) the 'classic' Shortwave Antenna was the so-called Longwire Antenna. [ RadioShack - Outdoor Antenna Kit for Shortwave Radios ]
On 14 Mar 2006 01:52:50 -0800, "RHF"
wrote: MK - For the Shortwave Listener (SWL) the 'classic' Shortwave Antenna was the so-called Longwire Antenna. CLASSIC - SHORTWAVE LONGWIRE ANTENNA {KIT} A simple 50-100 Foot long piece of Bare Copper Wire plus a 30-50 Foot long piece of Insualted Copper Wire add a 5-15 Foot long piece of Solid Copper Ground Wire and a Cold Water Pipe Ground Strap. Add-in a few Insulators. With the 'complete' One Page of Instructions including a Diagram and Parts List. Now That Is A "CLASSIC" When It Comes To Shortwave Listening (SWL) Antennas and Shortwave Radios for the last 75-100 Years. Hey MK - It Is Such A "Classic" that RadioShack still offers one for sale today : * Outdoor Antenna Kit for Shortwave Radios RadioShack Catalog # 278-758 http://www.radioshack.com/product/in...ductId=2104088 mk - there are classics -and- Then There Are Classics ~ RHF [ A Shortwave Goodbye :] . You forgot the fire extinguisher. |
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