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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 |
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
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 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 |
Antenna for shortwave reception
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. However: *a matchbox will allow you to use a poorly designed/constructed antenna--it will NOT improve the antenna. *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.) *a matchbox CAN allow you to alter the electrical length of an antenna--physical and electrical lengths are two different animals. And, this is all-in-a-nut shell; as you realize, a proper education in this field is NOT a trivial thing. 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 |
Antenna for shortwave reception
Sum Ting Wong wrote:
On Sat, 27 Dec 2008 12:27:09 -0800, John Smith wrote: The same antenna which transmits the MOST EFFICIENT signal possible, will also receive the signal the MOST EFFICIENTLY If that were true then the BIG boys on 160m would have no need for tall vertical transmitting antennas and traveling wave (Beverage) receive antennas. They could just use one or the other for both transmitting and receiving, but they don't. That's because one is better for transmitting and one is better for receiving. S.T.W. That is simply ridiculous, as I stated, in any properly designed antenna, with the proper pattern to achieve the points in question, and able to handle xmitter power, and is the MOST efficient for the purpose at hand will be EQUALLY efficient in both transmitting and receiving ... On 160m, I have ALWAYS used the same antenna to transmit as to receive ... What I stated is ABSOLUTELY TRUE ... and, there is but one truth possible here. And, certainly, in the situation you stated above, a discrepancy (imbalance) has been, absolutely, induced, as one antenna will out preform the other, have a different pattern, etc. However, a beverage would NOT be my first choice for a transmitting antenna! And, certainly, there is no comparison over the directionality difference (i.e., patterns) between these two antennas! 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
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. |
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 |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur RadioAntennas
Dave wrote:
... 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. As I previously stated, works nicely on paper/software; in real life, I have not been able to construct an antenna which demonstrates an advantage to justify the difficulty of dealing with the extra length. Now, a 2m on down, why not "toss it on", just in case? Now, when loading a 1/4 wave physical length antenna to a 1/2 wave electrical length, I DO see an advantage, increased radiation resistance, minimal counterpoise required, etc. Even when taking into consideration the losses added by the coil ... Regards, JS |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
"Telamon" wrote in message ... In article , John Smith wrote: Billy Burpelson wrote: ... Say what? He said he "ain't here to be a ham", so why would he want to transmit? Well, consider me a "different type of ham." SNIP Yeah, you are a Trolling Ham and a well done one at that. And Telamon is just a newgroup troll....so he trumps you. |
Antenna for shortwave reception
John Smith wrote:
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 You're the guy from Lost in Space! |
Antenna for shortwave reception
Dave wrote:
... You're the guy from Lost in Space! And, since your reasoning and manners are so ALIEN to me ... oh my gawd, a real one! grin Regards, JS |
Antenna for shortwave reception
On Sat, 27 Dec 2008 21:24:44 GMT, "Dave" wrote:
efficiency is only one measure of antenna performance. Exactly. You get it and JS doesn't. S.T.W. |
Antenna for shortwave reception
Sum Ting Wong wrote:
On Sat, 27 Dec 2008 21:24:44 GMT, "Dave" wrote: efficiency is only one measure of antenna performance. Exactly. You get it and JS doesn't. S.T.W. Oh, "I get it", you guys just don't get the lack of importance to your point(s!) Correct match to you rig does NOT affect the antennas efficiency, you would still want the most efficient antenna. Antenna length does relate to efficiency, and normally you would erect the longest possible for the freqs, and the efficiency of the antenna is improve, if by nothing else, than capture area ... however, you must balance this against the antenna pattern you wish. The pattern of the antenna, which will be identical in both T/R, is important. Antenna efficiency is important. Match to feedline, and feedline to rig is important. You seem to feel that s/n ratio is something to pursue, I tell you it is not. This is actually handled in the antenna pattern, you do NOT want the antenna to be receptive in the direction(s) of noise sources nor have it prone to static charges and disturbance ... antenna design is what controls this. Your main problem is that you wish to separate all the elements out and be able to deal with each one separately--you can't, every added capacitance adds some measurable amount of inductance, every added inductance adds some measurable amount of capacitance. There is never a case when you wish to decrease antenna efficiency, well, unless you are attempting to construct a dummy load ... If the antenna is "too sensitive" (efficient), crank your rf gain down a bit to the noise floor ... However, if I was supporting a poor antennas' use, or selling a poor antenna, lack of attention to efficiency would be my first "selling point!" Let me repeat, there is NEVER a time a ham or swl'er will want lack of efficiency--they have rf gain controls and other "attenuation boxes" to handle that--you obviously are attempting to confuse antenna efficiency with another aspect of antennas ... indeed, efficiency can be applied to most aspects of an antenna, i.e., "most efficient length", "most efficient match", "most efficient placement", "most efficient design", "most efficient pattern", etc.--and these CAN all vary as to the antennas intended use ... you can never make one change in antenna design which DOES NOT affect all others--i.e., one change makes many ... it is why EZNEC and MMANA-GAL are so desirable to toy with ... load up the software, make one change, watch it affect all others ... well, most of the time. Regards, JS |
Antenna for shortwave reception
Sum Ting Wong wrote:
On Sat, 27 Dec 2008 21:24:44 GMT, "Dave" wrote: efficiency is only one measure of antenna performance. Exactly. You get it and JS doesn't. S.T.W. Now, to sum that previous post up tightly, and it the hopes you "may get it" THIS TIME ... you NEVER want a less efficient antenna--in the fact that efficiency relates to transferring power to and from the ether. Or, in the case you wish to focus upon, "efficiency = ability to pluck incredibly weak signals from the ether." Any other argument, is simply to replace a respectable antenna with a dummy load or a partial dummy load; and, is not something which is usually argued against, by sane men ... Regards, JS |
Antenna for shortwave reception
In article , Dave
wrote: John Smith wrote: 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 ... You're the guy from Lost in Space! You are to kind Dave. The lost in Space Dr. Smith fooled some of the people some of the time where our Smith fools none of the people none of the time. -- Telamon Ventura, California |
The Difference Between : Shortwave Radio Listener (SWL) -and- AmateurRadio Operators (Hams)
On Dec 28, 12:14*pm, John Smith wrote:
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 JS - You started using 'Car' Analogy; and I followed through with 'Car' Analogy ~ RHF To many/most Hobbyists there 'hobbies are simply "Hobbies" : Some thing that they do in their spare time to enjoy and pass the time. Most Shortwave Radio Listeners (SWL) fit into this Category of Hobbyists. For some/many Hobbyists there 'hobby' is their true "Avocation" in-fact for some Their HOBBY is Their Life : Some thing that They Do All The Time : They Live and Breath Their Hobby : Many Amateur Radio Operators {Hams} fit into this Category of HOBBYISTS. http://www.answers.com/Avocation This is Why I refer to Amateur Radio as "The Craft" : The Mastery* of the Body of Knowledge and Practices related to the Science and Art of Radio Operating. * All Praise Be To Them That Do. -but- that is not me : for i remain simply a plain old shortwave radio listener : who keeps his swling "k-i-s-a-p" = keep/ing it simply and practical If some one asks "Where To Buy" : I tell them 'where to buy'. If some one asks "How To" {Build It} : I tell them 'how to' {build it} They Did Not Ask for "The Theory Behind It" -and- i don't give them 'the theory behind it' If some asks "What Do You "Recommend" : I 'recommend' a something or two and usually provide a few links as pointers to get them going. hey it is just my opinion and nothing more - kisap ~ RHF -ps- JS Yes You Are Right "I Am Extremely Special" ;-} |
The Difference Between : Shortwave Radio Listener (SWL) -and-Amateur Radio Operators (Hams)
RHF wrote:
[stuff] RHF, I have no bone to pick with you, don't fall victim to trolls here which just wish to "stir up chit", to mask their ignorance ... I had a chit load of ignorance (still do in many areas, including this one!), you don't know until you do ... we are all here on differing levels, we can all get along. When Roy, Cecil and others make statements, I LISTEN, may not understand it, but I listen! :-) I understand; trust me, you have done nothing to either make me like you, or not ... that may or may not come later. Now, this discussion continues ... Warm regards, JS |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
In article ,
John Smith wrote: 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 ... You dumb twit. We don't care about transmitting. Receiving is EQUALLY as important as the transmitting element in the above. Again you dumb twit, we don't care about transmitting. 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 ..." You are one funny guy I'll give you that. However, you mileage may vary with you "magical antenna logic!" grin The only magic around here is spouted by you. Your experience is "magically" different than anyone else's and your antenna theory is simplistic at best not to mention the great job you do of putting words in peoples mouthes never spoken but what else can we expect from the comprehension impaired. I'll tell you what is "magical" and that's the conversations you seem to have in your head before you post. 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 ... :-( Yeah, very sad of you to keep plonking and then continue to read me. What a goofball. -- Telamon Ventura, California |
Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
In article ,
John Smith wrote: 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. You have been very entertaining voice as usual though. -- Telamon Ventura, California |
Antenna for shortwave reception
On Sun, 28 Dec 2008 14:43:27 -0800, John Smith
wrote: You seem to feel that s/n ratio is something to pursue, I tell you it is not. You must have been one of the really strong stations I heard during the last ARRL 160m contest that kept calling CQ over and over without being able to hear all the stations that were answering you. It must have been frustrating. 73, S.T.W. |
Antenna for shortwave reception
Sum Ting Wong wrote:
... You must have been one of the really strong stations I heard during the last ARRL 160m contest that kept calling CQ over and over without being able to hear all the stations that were answering you. It must have been frustrating. 73, S.T.W. Hmmm, from your statements, and text--if adhered to, most-certainly suggests, they must be following your advise, surely! The "alligators", or, i.e., stations which are all mouth and no ears ... However, I am willing to debate, argue, stand-behind, etc., all which I have said ... I actually HAVE built my antennas, and continue to do so .... indeed, my statement is, "Only lamers buy them." Regards, JS |
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