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Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
RHF wrote:
... js - but alas i remain a simple shortwave listener who simply enjoys listening to the radio; cause practically speaking; that is what i do - - - respectfully ~ RHF . Quit peeing on my leg ... Brother, I enjoy having a good time, a good drink and the company of a good woman as well as anyone; And, furthermore, I am here because I enjoy a good antenna as well as anyone else. I am here because some know much more than me, can explain it in a manner which I can absorb (Cecil is but one example), and I expect there is much more for us ALL to learn, indeed ... I ain't here to lecture you ... I ain't here to be a ham ... I ain't here to play the game of "one-up-man-ship"; I am here to catch what I missed "the-first-time-around"--end-of-story. But now, a good argument, a good debate, a good "theory-session" ... count me in! Sit back, and pick on the next guy in line ... ;-) Regards, JS |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
RHF wrote:
... - - - respectfully ~ RHF . But, can I ask you one question?; You do pull on your pants one leg at a time, right? wink I mean, only politicians, as far as I know, claim different! LOL Regards, JS |
Antenna for shortwave reception
Roy Lewallen wrote: I can add a little information that might be helpful. When considering a receiving antenna, the single thing you need to be concerned about is signal to noise ratio. Unless your antenna is exceptionally poor and/or your receiver exceptionally noisy, making what you receive louder is just a matter of turning up the volume, or adding an audio amplifier if it's not loud enough. But it won't help you hear a station, because it and the noise will get louder in the same proportion. Quite a bit of what you'll read about antennas deals with improving antenna efficiency. That's because it's important when the antenna is used for transmitting. But when you use it for HF receiving, efficiency doesn't matter unless it gets to be bad enough that your receiver's noise becomes greater than the atmospheric noise it's receiving. Efficiency matters just as much on receive as it does on transmit. |
Antenna for shortwave reception
dxAce wrote:
... Efficiency matters just as much on receive as it does on transmit. Actually, even more! In fact, any antenna I have ever had, which receives well, transmits equally well ... the reverse is not always so; As, it is easy to pump more power into a bad antenna to make up for poor performance on xmit. Regards, JS |
Antenna for shortwave reception
On Dec 23, 9:46*am, PJ wrote:
Folks, I have purchased a Sangean ATS-909 World Receiver. It is equipped with an internal ferrite antenna för MW and LW, and a telescope antenna for SW and FM. It also comes with a portable SW antenna (ANT-60), seven meters long. Is this external antenna generally sufficient for SW reception, or should I get a different antenna? If yes, is there a solution that doesn't cost all that much money? I have a copy of the 2009 World Radio TV Handbook, and they are talking about a Wellbrook ALA-1530+ loop antenna, and let me tell you, that one is well past my budget, because it costs $466... I am looking for something a lot cheaper... :-) If it is recommended to replace the ANT-60, that is. PJ http://www.wellbrook.uk.com/ALA100b.html With a bit of hacking, the Wellbrook ALA 100 is as good as any of the shortwave antennas they sell. It is just the amplifier. You have to roll your own loop. The ALA100 is the lowest cost welbrook. At the current exchange rate, the ala100 is a over $200. I have made a few loops with this amp. I have a 2ftx2ft out of copper pipe for direction finding. I have 4ft x 6ft copper pipe for regular use. It's really stupid big and will eventually be reduced to the original 4ftx4ft. I have a few portable designs that are around 40ft worth of wire. The wellbrook loops are just amazing. All that said, the ATS909 probably can't handle that much signal. It would make sense to use one with a portable shortwave radio. |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
RHF wrote:
Dave, IIRC a good Amateur Radio 1/4 WL Vertical-Up-Leg by 1/4 WL Horizontal-Out-Arm {Inverted "L" Antenna requires very little Tuning and performs very well near and far on the HF Band that it is 'cut' to use on. Using a direct-connect or 1:1 UnUn at the Feed-Point * Half-Wave Inverted "L" Antenna : 1/4 WL + 1/4 WL Where-as the more common Shortwave Listener (SWL) type of {Random Wire} Inverted "L" Antenna is un-equal and usually has a shorter Vertical-Up-Leg and a longer Horizontal-Out-Arm of at least 1V-to-2H and often 1V-to-3H or more. Using a 9:1 Matching Transformer and Ground Rod at the Feed-Point which is at the base of the Vertical-Up-Leg. "Random" implies otherwise. Instead of a 9:1 UnUn, imagine one of these at the feed point: http://www.mfjenterprises.com/Produc...ductid=MFJ-927 I enjoy playing with these kind of things. So I got a license to transmit. Some call that "elitist", I call it self-indulgent. |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
John Smith wrote:
Dave wrote: ... A random wire (e.g. inverted L) transmits nicely if you use a tuner at the feed point. Nicely is rather a broad term ... And, if I am running 1KW+, or even multi-kilowatts, and the guy on the other end is doing the same--we can communicate "nicely" on very poor antennas ... However, if I am running 5 watts, and the other guy is also, a properly constructed antenna which has been designed around efficiency and most desirable radiation pattern, along with having a correct impedance and is matched EXACTLY to the equipment, and such is done without a lossy "matchbox" or inefficient matching method--these would be of paramount importance. Physics, as much as math, is an EXACT science ... antennas are NOT in realm of "art" (gray areas, open to interpretation, is a matter of personal opinion, etc.), there is but one "best" antenna for any given distance, terrain, pattern, etc. Regards, JS |
Antenna for shortwave reception
Dave wrote:
... You are not "pumping" any more "power" into a non-resonant antenna. Unless you are using a tuner you are heating up your finals. First, your use of "resonant" is just plain confusing ... All my multiband antennas, which I have ever use in life, are physically resonate on but one freq (or band.) On the others, they are only electrically resonate (and, lossy loading components are used to effect this.) A matchbox can always improve the reception on a poorly designed antenna, a mismatched antenna, a non-physically resonate antenna, etc. My 2m, 10m, 20m antennas are separate units. My 40m-80m-160 is a multiband, my neighbors and property limitations demand this ... and of course, a separate antenna, designed for a fairly narrow chunk of band would always be the most logical choice ... if possible. If I lived in an apartment and was forced to use one antenna for all bands, it could be done ... and would be better than nothing! Regards, JS |
Antenna for shortwave reception
Dave wrote:
... Not when you're talking about VSWR. Really? First time I have ever heard someone state that! Pray tell, what laws of physics come into play, which disrupts reality, when the antenna is fed from the ether (receiving), rather than developing its' load into the ether? (transmitting) Regards, JS |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Dave wrote:
... I don't recognize "politician" as being a monolithic culture. There are decent ones and there are many more ****-heads, but that holds true for society in general. I don't believe that. Simply because, in the last 30+ years, I have NEVER seen ANYTHING get any better--or, at least those things which are in the realm of things influenced by politics, legislation produced by politicians, or for that matter, ANYTHING done by politicians! They are there because of their desire for either money, power, or both. They support a shadow government solely for what benefits they, their family and friends get from the individuals in this elite group. Although, the above would be impossible to prove at this date; I believe a through awareness and study of the direction "things" constantly seem to be going in leaves one with no other possible conclusion(s) ... Regards, JS |
Antenna for shortwave reception
John Smith wrote:
Dave wrote: ... Not when you're talking about VSWR. Really? First time I have ever heard someone state that! Pray tell, what laws of physics come into play, which disrupts reality, when the antenna is fed from the ether (receiving), rather than developing its' load into the ether? (transmitting) Regards, JS "Pray tell"? Alas and alack. Zounds! Unfortunately, your editing is a bit severe and I have no idea what you're talking about. |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
JB wrote:
... Actually there is no reason TO have a resonant length antenna if you can tune it electrically. After all, you may want to tune around some. I can tell you it is a pain to have to go out and physically make adjustments for any frequency excursion. There are many nonresonant length antennas that outperform the resonant length. The 5/8 wave vertical comes to mind. A long-wire provides a larger capture area. Then there are phased arrays that reinforce. Look up the HAARP project and see how they made a very large array and were able to electrically steer the pattern. Cool! The more you know, the cheaper it gets, and the more you giggle when it works. The only problem is you get hooked and want to do so much more. Well, examine a mechanical tuning fork. They are cut to an exact physical length for resonance, the are very sharp tuning. Now, it would be possible to "lengthen" such a tuning fork with some coil of material, or portion of a turn of material. There is a reason for this; as, although it could be done, it would not be as efficient as one cut to the exact length; plus, you would induce a high probability of increased harmonics as a freq(s) which the fork was not created to induce ... there are exact equivalents in the electrical world of RF ... As you point out, physical length resonance is NOT a requirement ... it is simply "best" ... Regards, JS |
Antenna for shortwave reception
On Dec 27, 6:14*pm, John Smith wrote:
Dave wrote: ... You are not "pumping" any more "power" into a non-resonant antenna. Unless you are using a tuner you are heating up your finals. First, your use of "resonant" is just plain confusing ... All my multiband antennas, which I have ever use in life, are physically resonate on but one freq (or band.) *On the others, they are only electrically resonate (and, lossy loading components are used to effect this.) A matchbox can always improve the reception on a poorly designed antenna, a mismatched antenna, a non-physically resonate antenna, etc. John Smith, OK then what is a 'matchbox' in : * a poorly designed transmitting antenna, * a mismatched transmitting antenna, * a non-physically resonate transmitting antenna, Consider the 'matchbox' to be one element in the RF Energy Radiating System : Feed-Line + 'matchbox' + Antenna Element i want to know - iane ~ RHF |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
John Smith wrote:
Dave wrote: ... I don't recognize "politician" as being a monolithic culture. There are decent ones and there are many more ****-heads, but that holds true for society in general. I don't believe that. Simply because, in the last 30+ years, I have NEVER seen ANYTHING get any better--or, at least those things which are in the realm of things influenced by politics, legislation produced by politicians, or for that matter, ANYTHING done by politicians! They are there because of their desire for either money, power, or both. They support a shadow government solely for what benefits they, their family and friends get from the individuals in this elite group. Although, the above would be impossible to prove at this date; I believe a through awareness and study of the direction "things" constantly seem to be going in leaves one with no other possible conclusion(s) ... Regards, JS You pretend to be powerless to fight this... |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Dave wrote:
John Smith wrote: RHF wrote: ... js - but alas i remain a simple shortwave listener who simply enjoys listening to the radio; cause practically speaking; that is what i do - - - respectfully ~ RHF . Quit peeing on my leg ... Brother, I enjoy having a good time, a good drink and the company of a good woman as well as anyone; And, furthermore, I am here because I enjoy a good antenna as well as anyone else. I am here because some know much more than me, can explain it in a manner which I can absorb (Cecil is but one example), and I expect there is much more for us ALL to learn, indeed ... I ain't here to lecture you ... I ain't here to be a ham ... I ain't here to play the game of "one-up-man-ship"; I am here to catch what I missed "the-first-time-around"--end-of-story. But now, a good argument, a good debate, a good "theory-session" ... count me in! Sit back, and pick on the next guy in line ... ;-) Regards, JS A random wire (e.g. inverted L) transmits nicely if you use a tuner at the feed point. A resonate 1/4 wave dipole transmits "nicely" and uses no lossy tuner .... a resonate 1/4 wave vertical monopole, with drooping ground plane, transmits "nicely", requires no lossy tuner, and is damn near a perfect match to 50 ohm coax ... A 1/2 wave version of either of the above produces a superior pattern and can be matched with either a T-match or gamma-match ... indeed, a very minimal counterpoise is all which is necessary--and, if things are "perfect", not even that is needed, or simply a choke on they outside of the coax a ~1/4 wave away from feed point. A 5/8 is non-resonate physical length, and even demonstrates a superior pattern (at least on paper and with antenna prediction software ... ) However, in side-by-side comparisons on 10-6-2m antennas I have built, comparing a 5/8 against the 1/2 (construction methods/materials and matching components identical) ... the actual difference, in the real world, must be less than the width of a meter needle in the readings ... or, put simply, I no longer deal with the extra length required of the 5/8 ... your mileage may vary ... Regards, JS |
Antenna for shortwave reception
In article ,
Dave wrote: John Smith wrote: Dave wrote: ... Not when you're talking about VSWR. Really? First time I have ever heard someone state that! Pray tell, what laws of physics come into play, which disrupts reality, when the antenna is fed from the ether (receiving), rather than developing its' load into the ether? (transmitting) Regards, JS "Pray tell"? Alas and alack. Zounds! Unfortunately, your editing is a bit severe and I have no idea what you're talking about. He thinks transmitting and receiving antenna engineering is the same thing and reciprocity rules all consideration thereof capture area be damned. That's what happens when you have a pointy head. Go ahead though as he loves to argue about pointless things. -- Telamon Ventura, California |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
In article ,
Dave wrote: John Smith wrote: Dave wrote: ... A random wire (e.g. inverted L) transmits nicely if you use a tuner at the feed point. Nicely is rather a broad term ... And, if I am running 1KW+, or even multi-kilowatts, and the guy on the other end is doing the same--we can communicate "nicely" on very poor antennas ... However, if I am running 5 watts, and the other guy is also, a properly constructed antenna which has been designed around efficiency and most desirable radiation pattern, along with having a correct impedance and is matched EXACTLY to the equipment, and such is done without a lossy "matchbox" or inefficient matching method--these would be of paramount importance. Physics, as much as math, is an EXACT science ... antennas are NOT in realm of "art" (gray areas, open to interpretation, is a matter of personal opinion, etc.), there is but one "best" antenna for any given distance, terrain, pattern, etc. Funny guy that Smith. He has entered the gray area of opinion as to what is best. -- Telamon Ventura, California |
Antenna for shortwave reception
RHF wrote:
... "N", Don't know too many 'Hams' would would take 50 Feet of common Speaker Wire and tie-a-knot at 30 Feet and then split the two Wires in the remaining 20 Feet and use the thing as a "Stealth" Dipole Antenna with their Transmitter -but- a Shortwave Radio Listener (SWL) can do that and have a very practical SWL Antenna to use with many 'portable' AM&FM Shortwave Radios. 50-Ft. 24-Gauge Clear 2-Conductor Speaker Wire RadioShack Catalog # 278-1301 http://www.radioshack.com/product/in...ductId=2102499 "n" - practically speaking {in practice} there is a difference between between hams and swls ~ RHF . . I have taken ordinary lamp zip cord, split the two leads apart to for a 1/4 wave dipole and fed the end of the remaining length of zip cord with a balun to the rig (some zip cord is ~68-72 ohm balanced line, the mismatch is more than acceptable for field/emergency use.) Never, say never ... some ham will do it! Regards, JS |
Antenna for shortwave reception
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Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
In article ,
Dave wrote: RHF wrote: Dave, IIRC a good Amateur Radio 1/4 WL Vertical-Up-Leg by 1/4 WL Horizontal-Out-Arm {Inverted "L" Antenna requires very little Tuning and performs very well near and far on the HF Band that it is 'cut' to use on. Using a direct-connect or 1:1 UnUn at the Feed-Point * Half-Wave Inverted "L" Antenna : 1/4 WL + 1/4 WL Where-as the more common Shortwave Listener (SWL) type of {Random Wire} Inverted "L" Antenna is un-equal and usually has a shorter Vertical-Up-Leg and a longer Horizontal-Out-Arm of at least 1V-to-2H and often 1V-to-3H or more. Using a 9:1 Matching Transformer and Ground Rod at the Feed-Point which is at the base of the Vertical-Up-Leg. "Random" implies otherwise. Instead of a 9:1 UnUn, imagine one of these at the feed point: http://www.mfjenterprises.com/Produc...ductid=MFJ-927 I enjoy playing with these kind of things. So I got a license to transmit. Some call that "elitist", I call it self-indulgent. Remote tuners are the right way to do things. Much better than a tuner in the shack. -- Telamon Ventura, California |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Dave wrote:
... You pretend to be powerless to fight this... My single voice IS powerless against the sheer magnitude of the onslaught I would launch it against. However, the power of my voice combined with thousands, tens-of-thousands, hundreds-of-thousands ... of other voices eventually can and does make changes; and, is as it should be. Regards, JS |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Telamon wrote:
... Yeah but we don't care about transmitting goofball, we care about receiving and so that statement "A random wire (e.g. inverted L) transmits nicely if you use a tuner at the feed point" by Dave is relevant where you are not. You ridiculous fool. You are the most complete brain dead example of a sub-human which has ever been presented to me ... Receiving is EQUALLY as important as the transmitting element in the above. Or, to explain it to the necessary point, for a mental midget, such as yourself: "If the signal being transmitted is low power, or there are bad conditions, and, perhaps, the guy is in Australia, I'd better have the "best" antenna possible. However, if I am receiving the "50,000 watt atmosphere burner", 50 miles away, a rusty coat-hanger, most likely, would work ..." However, you mileage may vary with you "magical antenna logic!" grin You hit me as a guy attempting to pass off "magical physics" to kindergarten-ers; but then, even that is, most likely, a challenge for you ... sad, so very, very sad ... :-( plonk ... Regards, JS |
Antenna for shortwave reception
On Dec 27, 8:44*pm, John Smith wrote:
RHF wrote: OK then what is a 'matchbox' in : * a poorly designed transmitting antenna, * a mismatched transmitting antenna, * a non-physically resonate transmitting antenna, Consider the 'matchbox' to be one element in the RF Energy Radiating System : Feed-Line + 'matchbox' + Antenna Element - - i want to know - iane ~ RHF - - *. - It would be far more "in the realm of correct" to - consider what a matchbox DOES, rather than - what it IS--as it is simply some combination - of inductive and capacitive components which - ALWAYS will induce some form of loss into - any system it is inserted into. Yeah - Once it is 'placed' in the "System" the MatchBox becomes part of the "System" and becomes one of the loses within the "System" - However: - *a matchbox will allow you to use a poorly designed/ - constructed antenna--it will NOT improve the antenna. Now -if- That is True : Then Why Us The MatchBox within an RF Energy Radiating System ? - *a matchbox will allow you to "match" differing - impedances to achieve proper power transfer to - the antenna--again, it will NOT improve the - efficiency of that antenna, and the power will be - "simply lost" (as heat.) So you are say that a MatchBox will not improve the ERP of an RF Energy Radiating System ? And that the Receiving Station will not hear you 'better' when the MatchBox is properly used with the RF Energy Radiating System ? - *a matchbox CAN allow you to alter the electrical - length of an antenna--physical and electrical lengths - are two different animals. Electrical Characteristics = 'apparent electrical length' - And, this is all-in-a-nut shell; - as you realize, a proper education - in this field is NOT a trivial thing. A proper education in 'any' field is not a trivial thing. And that education can take many forms : formal practical, vocational {life time of work} and avocation {life time hobby} - That said, I frequently carry a cheap portable with me on trips and - launch a longwire into a tree, etc., find acceptable signals and enjoy - listening ... or else, just grab the SW stations audio from the net ... - being an old-timer, the first is more enjoyable, for me. - - Regards, - JS being an old timer myself - i still find simply listening to the radio to be enjoyable ~ RHF |
Antenna for shortwave reception
On Dec 27, 6:45*pm, Dave wrote:
John Smith wrote: Dave wrote: * ... Not when you're talking about VSWR. Really? *First time I have ever heard someone state that! Pray tell, what laws of physics come into play, which disrupts reality, when the antenna is fed from the ether (receiving), rather than developing its' load into the ether? (transmitting) Regards, JS "Pray tell"? - Alas and alack. *Zounds! Dave "Zounds!" - by golly wally - that is one you don't hear to often these days ~ RHF http://img141.imageshack.us/img141/9759/23oq.jpg Unfortunately, your editing is a bit severe and I have no idea what you're talking about. |
Antenna for shortwave reception
RHF wrote:
... Yeah - Once it is 'placed' in the "System" the MatchBox becomes part of the "System" and becomes one of the loses within the "System" ... Actually, the ONLY reason to use a matchbox is that the antenna is less than optimal for the freq(s) in question, end-of-story. However, multi-band operation and simply having to cover a wide swath of frequencies makes this the logical way to go, a matchbox ... in an ideal situation, a matchbox would be avoided. Now -if- That is True : Then Why Us The MatchBox within an RF Energy Radiating System ? There is nothing magical about a transmitting antenna, like I stated earlier, the exact same physics govern that antenna in receive or xmit modes. The matchbox allows you to achieve "maximum POOR performance" from the POOR antenna ... ... So you are say that a MatchBox will not improve the ERP of an RF Energy Radiating System ? And that the Receiving Station will not hear you 'better' when the MatchBox is properly used with the RF Energy Radiating System ? ... I said NO such thing, indeed, I stated the EXACT opposite, it allows maximum power transfer to the antenna, however, the losses in the POOR antenna are now increased due to the losses in the matchbox--as heat. And, no problems which exist in the POOR antenna have been rectified, they are just masked ... ... Electrical Characteristics = 'apparent electrical length' ... As I stated before, physical length need not be related to electrical length, however, in the most efficient design possible, they WILL be ... and that is only considering maximum transfer of power to the antenna, not, necessarily, the ether--and, that is NOT necessarily related to a desirable pattern of radiation of that power from the POOR antenna--the patten, IMHO, is governed, mainly, by antenna length and shape, however, some designs actually can cheat this, at least a bit. - And, this is all-in-a-nut shell; - as you realize, a proper education - in this field is NOT a trivial thing. ... being an old timer myself - i still find simply listening to the radio to be enjoyable ~ RHF . . As I stated before, a complete explanation/understanding of all factors involved defies a simple explanation ... as, if that were possible, no one would spend years in college, they could attend a week or a month and come away an expert. And, my field is computer science, this is all just a hobby with me. The little knowledge which I have assembled has been done over the course of years, even decades. I am hear to find out just "how deep this rabbit hole goes ..." Regards, JS |
Antenna for shortwave reception
On Dec 27, 7:46*pm, John Smith wrote:
wrote: Well, sure, but what does transmitting have to do with anything? We are not talking about transmitting. * ... It has EVERYTHING to do with it, it is the same communication, both ways, simply in reverse ... like I have stated before, the exact same laws of physics governing the antenna makes it equally acceptable to both transmitting and receiving. *The same pattern seen in the signal transmitted will be seen in the signal(s) received. - Your argument is the equivalent to arguing that - a car designed to go forward would not be - acceptable when backing up ... - simply ridiculous! - - Regards, - JS JS -think-about-it- IF 'by-design' the Car is in-fact designed to go "Only" Forward : * It may 'only' have Forward Gears and a Transmission that has NO Reverse. * No Rear Window * No Rear Mirror NOT So Ridiculous ~ RHF http://www.prweb.com/prfiles/2006/10...onmeteor72.jpg |
Antenna for shortwave reception
RHF wrote:
Consider the 'matchbox' to be one element in the RF Energy Radiating System : Feed-Line + 'matchbox' + Antenna Element i want to know - iane ~ RHF . It depends where the current node[s] end[s] up. |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
John Smith wrote:
However, in side-by-side comparisons on 10-6-2m antennas I have built, comparing a 5/8 against the 1/2 (construction methods/materials and matching components identical) ... the actual difference, in the real world, must be less than the width of a meter needle in the readings ... or, put simply, I no longer deal with the extra length required of the 5/8 ... your mileage may vary ... Regards, JS The advantage of a physical height (antenna length) between 180 and 215 degrees (see previous post regarding the magic number being around 195 degrees) is improved take-off angle and reduced skywave-groundwave interaction, not dramatic nearfield voltage increases. |
Antenna for shortwave reception
John Smith wrote:
RHF wrote: ... "N", Don't know too many 'Hams' would would take 50 Feet of common Speaker Wire and tie-a-knot at 30 Feet and then split the two Wires in the remaining 20 Feet and use the thing as a "Stealth" Dipole Antenna with their Transmitter -but- a Shortwave Radio Listener (SWL) can do that and have a very practical SWL Antenna to use with many 'portable' AM&FM Shortwave Radios. 50-Ft. 24-Gauge Clear 2-Conductor Speaker Wire RadioShack Catalog # 278-1301 http://www.radioshack.com/product/in...ductId=2102499 "n" - practically speaking {in practice} there is a difference between between hams and swls ~ RHF . . I have taken ordinary lamp zip cord, split the two leads apart to for a 1/4 wave dipole and fed the end of the remaining length of zip cord with a balun to the rig (some zip cord is ~68-72 ohm balanced line, the mismatch is more than acceptable for field/emergency use.) Never, say never ... some ham will do it! Regards, JS Yes,some ham will do it, with a 3 Watt transmitter tucked into a Sucrets tin, and work 50 countries with his zip cord dipole. |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Telamon wrote:
In article , Dave wrote: RHF wrote: Dave, IIRC a good Amateur Radio 1/4 WL Vertical-Up-Leg by 1/4 WL Horizontal-Out-Arm {Inverted "L" Antenna requires very little Tuning and performs very well near and far on the HF Band that it is 'cut' to use on. Using a direct-connect or 1:1 UnUn at the Feed-Point * Half-Wave Inverted "L" Antenna : 1/4 WL + 1/4 WL Where-as the more common Shortwave Listener (SWL) type of {Random Wire} Inverted "L" Antenna is un-equal and usually has a shorter Vertical-Up-Leg and a longer Horizontal-Out-Arm of at least 1V-to-2H and often 1V-to-3H or more. Using a 9:1 Matching Transformer and Ground Rod at the Feed-Point which is at the base of the Vertical-Up-Leg. "Random" implies otherwise. Instead of a 9:1 UnUn, imagine one of these at the feed point: http://www.mfjenterprises.com/Produc...ductid=MFJ-927 I enjoy playing with these kind of things. So I got a license to transmit. Some call that "elitist", I call it self-indulgent. Remote tuners are the right way to do things. Much better than a tuner in the shack. A tuner in the shack matches the radio to the transmission line. There is still a mismatch at the feedpoint. |
Antenna for shortwave reception
John Smith wrote:
Dave wrote: ... "Pray tell"? Alas and alack. Zounds! Unfortunately, your editing is a bit severe and I have no idea what you're talking about. Well, if you can't remember your own text, nor your "side" of an argument, between posts--I think it is all for moot ... Regards, JS Like you're the only person I talk with... |
Antenna for shortwave reception
John Smith wrote:
I said NO such thing, indeed, I stated the EXACT opposite, it allows maximum power transfer to the antenna, however, the losses in the POOR antenna are now increased due to the losses in the matchbox--as heat. And, no problems which exist in the POOR antenna have been rectified, they are just masked ... That is vastly oversimplified. |
KC8QJP felon tax fraud -was- Antenna for shortwave reception
"KC8QJP" wrote in message . .. "Richard Clark" wrote in message ... On Tue, 23 Dec 2008 09:46:07 -0800 (PST), PJ wrote: Folks, I have purchased a Sangean ATS-909 World Receiver. It is equipped with an internal ferrite antenna för MW and LW, and a telescope antenna for SW and FM. It also comes with a portable SW antenna (ANT-60), seven meters long. Is this external antenna generally sufficient for SW reception, or should I get a different antenna? If yes, is there a solution that doesn't cost all that much money? I have a copy of the 2009 World Radio TV Handbook, and they are talking about a Wellbrook ALA-1530+ loop antenna, and let me tell you, that one is well past my budget, because it costs $466... I am looking for something a lot cheaper... :-) If it is recommended to replace the ANT-60, that is. PJ Hi PJ, With your location in Sweden, a long wire should pick up a lot of stations unless you are buried deep in a valley. That long wire can be as simple as 10 meters of wire with a clip to attach it to the whip of the Sangean. When I was in Africa last year, that was enough to fill my cheap SW set with signals from everywhere in Africa up into Europe. Toss the wire out a window up into a tree. It is at least a cheap, first attempt to see if you need anything more than that. 73's Richard Clark, KB7QHC try the superskyhook sloper it works wonders over hear! http://i40.tinypic.com/2ykgg05.jpg mary xmas That looks like junk,KC8QJP . You're better off sticking to the bogus tax returns or are you still in prison for that? FORMAL DISCIPLINARY HEARING-KATHLEEN R. LEE Chairman Woods noted that Kathleen Lee was issued CPA certificate 36,525 on July 15, 1998. The hearing was to consider disciplinary action against Ms. Lee's CPA certificate pursuant to Ohio Revised Code section 4701.16(A)(5), conviction of a felony under the laws of any state or of the United States. Ms. Lee was convicted in the United States District Court, Northern District of Ohio of five counts of Aiding & Assisting in Filing False Tax Returns, a violation of 26 USC 7206(2), on June 12, 2000. Ms. Lee did not appear at the hearing. The Board agreed to deliberate the disciplinary action in a later executive session. Action taken. Kathleen R. Lee, CPA 4701.16(A)(5)-Convicted of aiding & assisting in filing of false tax returns. CPA certificate revoked. |
Antenna for shortwave reception
On Dec 28, 4:02*am, RHF wrote:
"N" - Alas in my heart I am still "that" 8-Year-Old that gets daily joy from DXing the AM-BCB and the Shortwave Bands; and more importantly simply listening to the radio : One Word "Enjoyment". "N" - You over time have evolved and grow with The Craft -while- I still simply enjoy it's less technical aspects as a user : We are different and therefore naturally see things differently. ~ RHF *. I was pretty primitive in the early days. :/ Not much money, so I made do with some weird stuff. Here is my "radio room" when I was in the 7th, 8th grade or so. Probably about 1971. The "room" is the closet in my bedroom.. http://home.comcast.net/~nm5k/r2.jpg The radio was a philco portable. Covered 4-12 mhz. No BFO.. So... I would use the white AM radio sitting behind it as a BFO. :/ Not the most fun in the world, being neither radio was the most stable things around.. But it would let me listen to CW and SSB with tuning tweaks every once in a while. Well, maybe more than once in a while.. :( The other white AM radio to the left was more for the clock, and I used the radio in it for local AM listening most of the time. The antenna was just a random wire strung out the back window. The contraption in the foreground was the first transmitter I built. It was a single 6V6 run off line voltage for the B+. Did maybe 5-10 watts I guess.. 40m, and I had two crystals. Look at my advanced scotch tape coil forming construction. :/ The chassis was WW2 Navy issue.. The circuit from the 1949 ARRL handbook. Yes, it actually worked.. :) I later rebuilt it using a transformer, and a bit more power. I used it as my first novice transmitter for a good while. By that time, I had a Hammarlund HQ-110 for a receiver. But as a SWL, I listened to half a zillion stations just with that little philco portable and about 50 feet of wire hooked to it. Spent half a fortune "to me back then" on IRC's to get faster QSL replies. You can see a RAI card on the wall. They sent me magazines for about 20 years after that card.. I still got color RAI magazines into the late 80's at least.. For many years, I used to get a Christmas card from Radio Havana.. Every year.. Then like the RAI mags, they finally quit coming. I used to get some real nice glossy color magazines from China back in those days. :/ The FBI probably thought I was some kind of communist being I used to get so much mail from them... |
Antenna for shortwave reception
RHF wrote:
... JS - What you call a "simplistic manner" IMHO is a will 'crafted' answer by "RL" designed to answer the readers question in a 'manner' that the reader could easily understand, accept and act-on. communications is about speaking 'to' the reader : not 'at' them - iane ~ RHF . I have no problem with the way Roy presented the material ... and, I believe there is high probability that you are correct, some people are more concerned with how material is delivered rather than the material itself ... I don't do well in those situations. And, I wish to accept no responsibility in having to participate, it makes for too much work. I simply wish to cut to the heart and deliver the material in a manner I prefer, I am sure there some who prefer the importance of material over the presentation ... Regards, JS |
Antenna for shortwave reception
Dave wrote:
John Smith wrote: I said NO such thing, indeed, I stated the EXACT opposite, it allows maximum power transfer to the antenna, however, the losses in the POOR antenna are now increased due to the losses in the matchbox--as heat. And, no problems which exist in the POOR antenna have been rectified, they are just masked ... That is vastly oversimplified. Absolutely, and at some point I must trust the reader has the resources to extrapolate; otherwise, all postings would soon turn in to the length, depth and completeness of a college textbook ... For example, an antenna is a two lane road, running in both directions(T/R), the same parameters which allow it to be the best choice for transmitting, also are in action when that same antenna "plucks" its' signals from the ether ... something I have pointed out in multiple ways, multiple times ... The average person must hear, read, study the same material six times before "learning" it. And, an instructor once pointed out to me, not all people respond to the same method, personality, mode-of-presentation as another or others ... so, he pointed out the importance of gathering data from multiple sources until the "epiphany" is realized ... Regards, JS |
Antenna for shortwave reception
RHF wrote:
On Dec 27, 7:46 pm, John Smith wrote: wrote: Well, sure, but what does transmitting have to do with anything? We are not talking about transmitting. ... It has EVERYTHING to do with it, it is the same communication, both ways, simply in reverse ... like I have stated before, the exact same laws of physics governing the antenna makes it equally acceptable to both transmitting and receiving. The same pattern seen in the signal transmitted will be seen in the signal(s) received. - Your argument is the equivalent to arguing that - a car designed to go forward would not be - acceptable when backing up ... - simply ridiculous! - - Regards, - JS JS -think-about-it- IF 'by-design' the Car is in-fact designed to go "Only" Forward : * It may 'only' have Forward Gears and a Transmission that has NO Reverse. * No Rear Window * No Rear Mirror NOT So Ridiculous ~ RHF http://www.prweb.com/prfiles/2006/10...onmeteor72.jpg . Just an Example of "Single Focus" Thinking : Optimizing Your Results For One Purpose. Sort of what Shortwave Radio Listeners (SWL) do when they consider how they are going to Design, Build and Use an Antenna for the Hobby of Shortwave Radio Listening (SWLing) Yes as you have pointed out : There is a Greater Boby of Knowledge and Practicum Out There That Could Be Considered and Used -but- The Shortwave Listener (SWL) often is 'selective' in what they consider and use to achieve their specific limited goals. It Has To Do With "Level-of-Involvement" : * Many/Most Amateur Radio Operators {Hams} have the well earn knowledge and experience to function 'like' an Auto Mechanic -wrt- Cars * * Hams at their best are Advocates of the Technology [ Practicers of The Craft ] * Many/Most Shortwave Radio Listeners (SWLs) simply enjoy a level of knowledge and experience to function 'like' a Car Driver -wrt- Cars * * SWLs at their best are Hobbyists Enjoyers of the Technology [ Users of the Technology ] TBL : Both are Need -and- Both are Different ~ RHF . I see you are ready to go to extraordinary lengths to justify your statements or propose "special cases" which are only correct in extreme circumstances of very limited parameters--this is all fine, however, carry on without me ... Again, it is as true as when I originally stated it, the same antenna, its efficiency, fitness-for-purpose, pattern delivered, etc. will work the same, both forward (transmitting), or in reverse (receiving.) I am sure there exists the possiblily of "breaking" or "orchastrating" the antenna physics to bring about a special case or cases ... no practical use I have yet seen has required this. Many hams wish to think themselves "special" because of their hobby, now you have brought me to the realization that there is the equivalent in the SWL'ers hobby ... to me, it just looks like one of my other hobbies, like tropical fish, for example. Regards, JS |
Antenna for shortwave reception
Dave wrote:
John Smith wrote: wrote: Well, sure, but what does transmitting have to do with anything? We are not talking about transmitting. ... It has EVERYTHING to do with it, it is the same communication, both ways, simply in reverse ... like I have stated before, the exact same laws of physics governing the antenna makes it equally acceptable to both transmitting and receiving. The same pattern seen in the signal transmitted will be seen in the signal(s) received. Your argument is the equivalent to arguing that a car designed to go forward would not be acceptable when backing up ... simply ridiculous! Regards, JS How does one transmit MW with a ferrite bar antenna? I have come across data on the net of people using ferrite loops for transmitting, a comprehensive google search should provide those to you .... personally, I have never had interest or need ... Regards, JS |
Antenna for shortwave reception
Dave wrote:
... I have taken ordinary lamp zip cord, split the two leads apart to for a 1/4 wave dipole and fed the end of the remaining length of zip cord with a balun to the rig (some zip cord is ~68-72 ohm balanced line, the mismatch is more than acceptable for field/emergency use.) Never, say never ... some ham will do it! Regards, JS Yes,some ham will do it, with a 3 Watt transmitter tucked into a Sucrets tin, and work 50 countries with his zip cord dipole. Now, I'd say, "That's the spirit!" Warm regards, JS |
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