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"Ionic Liquid" Antenna
Below is a link to a video describing the development work on an
interesting concept for an antenna: http://www.youtube.com/watch?v=9tIZUhu21sQ RF |
"Ionic Liquid" Antenna
On Sep 6, 9:56*am, Richard Fry wrote:
Below is a link to a video describing the development work on an interesting concept for an antenna: *http://www.youtube.com/watch?v=9tIZUhu21sQ RF magnetic coupling to the stream seems kind of odd, but it appears to work for him. i wonder what happens if you go qro? i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. i would also guess the tuning would be difficult in high winds. |
"Ionic Liquid" Antenna
On Sep 6, 10:59*am, K1TTT wrote:
On Sep 6, 9:56*am, Richard Fry wrote: Below is a link to a video describing the development work on an interesting concept for an antenna: *http://www.youtube.com/watch?v=9tIZUhu21sQ RF magnetic coupling to the stream seems kind of odd, but it appears to work for him. *i wonder what happens if you go qro? *i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. *i would also guess the tuning would be difficult in high winds. If anything is to occur it would be at the toroid which the water is flowing thru. In this case the diamagnetic material is the prime mover with respect to toroidal field. What the feed line is doing is not mentioned and it could well be the toroid windings alone is doing all the radiating |
"Ionic Liquid" Antenna
On 9/6/2010 10:28 AM, Art Unwin wrote:
... What the feed line is doing is not mentioned and it could well be the toroid windings alone is doing all the radiating Watch the video again. If we can believe that the video has not been manipulated then, the signals are not present until the water flows ... I seen this done many moons ago with a thick quartz tube(s) and a column of mercury, mercury height varied to tune ... I'll bet the "mercury" antenna is/was immensely more efficient ... the magnetic coupling would be a great aid in NOT having to tune the match constantly ... Regards, JS |
"Ionic Liquid" Antenna
On 9/6/2010 8:59 AM, K1TTT wrote:
magnetic coupling to the stream seems kind of odd, but it appears to work for him. i wonder what happens if you go qro? i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL |
"Ionic Liquid" Antenna
On Sep 6, 2:00*pm, Roy Lewallen wrote:
On 9/6/2010 8:59 AM, K1TTT wrote: magnetic coupling to the stream seems kind of odd, but it appears to work for him. *i wonder what happens if you go qro? *i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. *i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL Part of the speal given talked about the scarecity of real estate for the many antennas on ships! Why don't they use non frequency dependent antennas so antennas can be shared, especially when in combat? And what do submarines use for antennas when in the stealth mode? |
"Ionic Liquid" Antenna
"Richard Fry" wrote in message ... Below is a link to a video describing the development work on an interesting concept for an antenna: http://www.youtube.com/watch?v=9tIZUhu21sQ On 7 MHz a dipole constructed of salt water: Er = 81, conductivity 5 S/m, and 0.5" diameter has a free space efficiency of 0.08%. i.e. with 100 W input the total radiated power = 80 mW. Frank (VE6CB) |
"Ionic Liquid" Antenna
On 9/6/2010 4:41 PM, Art Unwin wrote:
... Part of the speal given talked about the scarecity of real estate for the many antennas on ships! Why don't they use non frequency dependent antennas so antennas can be shared, especially when in combat? And what do submarines use for antennas when in the stealth mode? Antennas which pop up out of the deck plating would be something. That idiot has just developed a very expensive toy ... and a very poor one at that. Regards, JS |
"Ionic Liquid" Antenna
Richard Clark wrote:
On Mon, 6 Sep 2010 02:56:49 -0700 (PDT), Richard Fry wrote: interesting concept for an antenna: "How's my signal?" "You've got a strong signal in, 5X5." ....this through a repeater - DUH. An HF antenna would need to put up a water stream "about 60 feet." Hmmm, about 3kPa for each foot of water or about 200kPa. At Walmart, for $320 you can buy a pump with a 2HP motor to do the job: 230V @ 11.2A Takes a lot more HP to make a free flowing fountain that high. Jet d'Eau in Geneva is 500 liter/sec with 2 500kW pumps (of course it is 140 meters tall)..(And yes, it is very impressive from a distance..) The Buckingham fountain in Chicago is shorter (ca 50 meters) and has much lower power pumps: 75,190 and 250 HP 2.5KW to erect the antenna for a 100W HF rig. If you stacked 50 HF rigs (end to end for more length), you would have both the same size antenna, plus ALL of the 2.5KW of power going to RF and not water. You can recover the energy in the water coming back down. If you have a tube, you can either just feed the conductive fluid up the tube and fill it (a sort of liquid SteppIR vertical), or, for fixed height, you could have a recirculation. This isn't particularly new or novel, by the way. The idea has been around for decades (I think I saw some papers from the 60s analyzing it). What's new is that the surrounding technology might have changed, and what was impractical back then might be more practical now. |
"Ionic Liquid" Antenna
On Tue, 07 Sep 2010 09:32:53 -0700, Jim Lux
wrote: An HF antenna would need to put up a water stream "about 60 feet." Hmmm, about 3kPa for each foot of water or about 200kPa. At Walmart, for $320 you can buy a pump with a 2HP motor to do the job: 230V @ 11.2A Takes a lot more HP to make a free flowing fountain that high. 60 feet is not in the league of 140 meters or the shorter 50 meters. However, to other comments, keeping it a column of water instead of spray would certainly add to the pump load. You can recover the energy in the water coming back down. Something like Hero's fountain? The proportions of this is growing by leaps and bounds. If you have a tube, you can either just feed the conductive fluid up the tube and fill it (a sort of liquid SteppIR vertical), or, for fixed height, you could have a recirculation. Which argues why not fill the tube with a tape measure instead? This isn't particularly new or novel, by the way. The idea has been around for decades (I think I saw some papers from the 60s analyzing it). What's new is that the surrounding technology might have changed, and what was impractical back then might be more practical now. The surrounding technology, literally, is the ferrite ring enclosing the column. In 1960's dollars, cheaper perhaps but nothing newer. And cheaper is relative - not particularly affordable. 73's Richard Clark, KB7QHC |
"Ionic Liquid" Antenna
On 9/6/2010 5:06 PM, Frank wrote:
On 7 MHz a dipole constructed of salt water: Er = 81, conductivity 5 S/m, and 0.5" diameter has a free space efficiency of 0.08%. i.e. with 100 W input the total radiated power = 80 mW. Frank (VE6CB) That looked so bad I had to run an analysis to see for myself. Sure enough, it's that bad. And even with a 0.25 inch diameter column at 146 MHz, the efficiency is only on the order of 1%. A foot and a half of wire vs. a pump, power source, and ferrite transformer? No contest. Roy Lewallen, W7EL |
"Ionic Liquid" Antenna
"Roy Lewallen" wrote in message ... On 9/6/2010 5:06 PM, Frank wrote: On 7 MHz a dipole constructed of salt water: Er = 81, conductivity 5 S/m, and 0.5" diameter has a free space efficiency of 0.08%. i.e. with 100 W input the total radiated power = 80 mW. Frank (VE6CB) That looked so bad I had to run an analysis to see for myself. Sure enough, it's that bad. And even with a 0.25 inch diameter column at 146 MHz, the efficiency is only on the order of 1%. A foot and a half of wire vs. a pump, power source, and ferrite transformer? No contest. Roy Lewallen, W7EL - Finally, something to make a T2FD look good :) Wayne W5GIE |
"Ionic Liquid" Antenna
On Sep 6, 11:41*pm, Art Unwin wrote:
On Sep 6, 2:00*pm, Roy Lewallen wrote: On 9/6/2010 8:59 AM, K1TTT wrote: magnetic coupling to the stream seems kind of odd, but it appears to work for him. *i wonder what happens if you go qro? *i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. *i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL Part of the speal given talked about the scarecity of real estate for the many antennas on ships! Why don't they use non frequency dependent antennas so antennas can be shared, especially when in combat? And what do submarines use for antennas when in the stealth mode? i would tell you, but then i would have to kill you! |
"Ionic Liquid" Antenna
K1TTT wrote:
On Sep 6, 11:41 pm, Art Unwin wrote: On Sep 6, 2:00 pm, Roy Lewallen wrote: On 9/6/2010 8:59 AM, K1TTT wrote: magnetic coupling to the stream seems kind of odd, but it appears to work for him. i wonder what happens if you go qro? i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL Part of the speal given talked about the scarecity of real estate for the many antennas on ships! Why don't they use non frequency dependent antennas so antennas can be shared, especially when in combat? And what do submarines use for antennas when in the stealth mode? i would tell you, but then i would have to kill you! Naahhh.. everyone knows they drag an insulated wire, which is why NEC was updated some years ago to handle insulated wires in a conductive medium. Now.. when their periscope is up, indeed, there's a lot of special stuff that goes into shared apertures. Look to the work of Jaumann in WWII.. And with sharing apertures.. it's not so much non-frequency dependent radiators that is the problem, it's isolation between the Tx and Rx. Multimegawatt pulses from your radar tend to raise cain with your sensitive receiver, even if your diplexer does have 100dB isolation. Finally, it is challenging to make something that can efficiently radiate at a frequency while not reflecting that same frequency (i.e. re-radiating). Brings a whole new meaning to "match at the feedpoint" when your RCS has to be a tiny, tiny fraction of the physical size. (for reference, the RCS of a resonant dipole with shorted feed is about 0.2 lambda^2) |
"Ionic Liquid" Antenna
On Sep 7, 7:03*pm, Jim Lux wrote:
K1TTT wrote: On Sep 6, 11:41 pm, Art Unwin wrote: On Sep 6, 2:00 pm, Roy Lewallen wrote: On 9/6/2010 8:59 AM, K1TTT wrote: magnetic coupling to the stream seems kind of odd, but it appears to work for him. *i wonder what happens if you go qro? *i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. *i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL Part of the speal given talked about the scarecity of real estate for the many antennas on ships! Why don't they use non frequency dependent antennas so antennas can be shared, especially when in combat? And what do submarines use for antennas when in the stealth mode? i would tell you, but then i would have to kill you! Naahhh.. everyone knows they drag an insulated wire, which is why NEC was updated some years ago to handle insulated wires in a conductive medium. Now.. when their periscope is up, indeed, there's a lot of special stuff that goes into shared apertures. *Look to the work of Jaumann in WWII.. And with sharing apertures.. it's not so much non-frequency dependent radiators that is the problem, it's isolation between the Tx and Rx. Multimegawatt pulses from your radar tend to raise cain with your sensitive receiver, even if your diplexer does have 100dB isolation. Finally, it is challenging to make something that can efficiently radiate at a frequency while not reflecting that same frequency (i.e. re-radiating). *Brings a whole new meaning to "match at the feedpoint" when your RCS has to be a tiny, tiny fraction of the physical size. (for reference, the RCS of a resonant dipole with shorted feed is about 0.2 lambda^2) As it happens I bought a nuclear submarine radio transmitter with only a few hours on it. It is a tube version so I assume the reason that it saw so little service was when they determined solid state was not an issue. Just for kicks today I put together 3 rolls of 50 conductor tape in series without unrolling them so the assembly was about 12 inches tall and 8 inches dia where as the antenna on the tower is about the size of a bow and arrow target and good for all bands without being frequency sensitive. Now the quick and dirty one was really 50 wires in parallel placed in series with end fed on two outside wires. Now it was only good down to and including 20 metres while sitting on the table next to the radio in a very cluttered shack with lots of equipment and on top of that it had no shield so you can't hang your hat on those results because of proximetry effect and other short cuts taken and yet the non frequency side of it is fully evident. So for a submarine or a ship in combat the long wire would leave an observable trace even when below the surface as the long wire will rise. Same goes for ships that have radiators in the double or triple figures where when damaged control can be transfered to other non frequency sensitive antennas. I served in the Army so I have little knoweledge as to what goes on in the Navy and thus the question posed. Certainly such a antenna would be a lot more stealth like than the water jet stream proposed on U tube or even a long wire leaving a trail on the surface for aircraft to zero upon. Regards Art |
"Ionic Liquid" Antenna
On 9/7/2010 7:04 PM, Art Unwin wrote:
... Just for kicks today I put together 3 rolls of 50 conductor tape in series without unrolling them so the assembly was about 12 inches tall and 8 inches dia where as the antenna on the tower is about the size of a bow and arrow target and good for all bands without being frequency sensitive. ... Regards Art Yeah, but can you shower with it? See, the other antenna doubles as a shower, just BYOS (Bring Your Own Soap.) Regards, JS |
"Ionic Liquid" Antenna
On Sep 7, 11:01*pm, John Smith wrote:
On 9/7/2010 7:04 PM, Art Unwin wrote: ... Just for kicks today I put together 3 rolls of 50 conductor tape in series without unrolling them so the assembly was about 12 inches tall and 8 inches dia where as the antenna on the tower is about the size of a bow and arrow target and good for all bands without being frequency sensitive. ... Regards Art Yeah, but can you shower with it? *See, the other antenna doubles as a shower, just BYOS (Bring Your Own Soap.) Regards, JS John, all non frequency dependent radiators have to be shielded as it plays havoc with the cancellation of reactance. But even with the quick lash up I made where I broke all the rules and even changed to "stacked pancakes" instead of coils inside coils it still would be ok for directional use in a loft for some of the bands. Either way the lash up did not totally destroy its attributes. I suppose it would be more impressive if I shielded it plus a reflector and put it on the tower but that was not the point I was trying to make which is the persistance in keeping non frequency dependentcy while maintaining a small volume. I modeled a ten turn coil inside another ten turn coil where both were joined together as a closed circuit and a overall diameter of 8 to 9 inches sitting on a perfect ground ala reflector When an antenna is not frequency dependent there is no skin depth resistance because of the Meissner effect so more current is applied to generating radiation. This conforming to Maxwell's law by not indulging in generating magnetic fields. Note Maxwell never added units of Tesla in his equation so why should you? By the way that model showed gain inbetween 20 and 30 db because of current bypassing the innards of the radiator and traveling on the surface. So the old timers were correct in saying more wire is better....as long as you decrease the resistance created by adding wire!!!!!! That way you have I sq R instead of I sq R + r which is efficiency in radiation to the maximum.by removing unnecessary losses. Simple concept eh? Regards Art |
"Ionic Liquid" Antenna
"Roy Lewallen" wrote in message ... On 9/6/2010 8:59 AM, K1TTT wrote: magnetic coupling to the stream seems kind of odd, but it appears to work for him. i wonder what happens if you go qro? i would expect some heating of the water and maybe even some ionization or corona that might cause instability in the stream. i would also guess the tuning would be difficult in high winds. Wind would seem to be a weak point. The top of the conductive stream would dissipate at different heights depending on the wind velocity, so a gusty wind would be constantly altering the effective antenna length. Roy Lewallen, W7EL Let's fix the wind problem and shorten the antenna! Have the water spray up into a receiving vessel the distributes the water into 5 or 6 radial tubes that make up a capacitive hat. :-) While we're at it, let's spray out some radials for a counterpoise! Hey, if we can catch all the water and recirculate it, then we can add material to increase the conductivity of the water. ok,ok I'll stop. MikeK |
"Ionic Liquid" Antenna
On 9/8/2010 9:27 AM, amdx wrote:
Let's fix the wind problem and shorten the antenna! Have the water spray up into a receiving vessel the distributes the water into 5 or 6 radial tubes that make up a capacitive hat. :-) While we're at it, let's spray out some radials for a counterpoise! Hey, if we can catch all the water and recirculate it, then we can add material to increase the conductivity of the water. ok,ok I'll stop. MikeK Let's just fill a tube with water and provide sufficient heat-sinking to keep the water at an acceptable temperature. Obviously, the idiot with the sump pump and walkie-talkie realized the power of the publics' fondness for toys ... Regards, JS |
"Ionic Liquid" Antenna
On Sep 7, 2:22*pm, Roy Lewallen wrote:
Sure enough, it's that bad. How many free electrons exist in ionized water? -- 73, Cecil, w5dxp.com |
"Ionic Liquid" Antenna
On 9/7/2010 11:52 PM, Art Unwin wrote:
John, all non frequency dependent radiators have to be shielded as it plays havoc with the cancellation of reactance. But even with the quick lash up I made where I broke all the rules and even changed to "stacked pancakes" instead of coils inside coils it still would be ok for directional use in a loft for some of the bands. Either way the lash up did not totally destroy its attributes. I suppose it would be more impressive if I shielded it plus a reflector and put it on the tower but that was not the point I was trying to make which is the persistance in keeping non frequency dependentcy while maintaining a small volume. I modeled a ten turn coil inside another ten turn coil where both were joined together as a closed circuit and a overall diameter of 8 to 9 inches sitting on a perfect ground ala reflector When an antenna is not frequency dependent there is no skin depth resistance because of the Meissner effect so more current is applied to generating radiation. This conforming to Maxwell's law by not indulging in generating magnetic fields. Note Maxwell never added units of Tesla in his equation so why should you? By the way that model showed gain inbetween 20 and 30 db because of current bypassing the innards of the radiator and traveling on the surface. So the old timers were correct in saying more wire is better....as long as you decrease the resistance created by adding wire!!!!!! That way you have I sq R instead of I sq R + r which is efficiency in radiation to the maximum.by removing unnecessary losses. Simple concept eh? Regards Art Boy, he's getting there fast. I bet he's around for less than 3 weeks this time. Any takers? tom K0TAR |
"Ionic Liquid" Antenna
On Sep 7, 12:22*pm, Roy Lewallen wrote:
On 9/6/2010 5:06 PM, Frank wrote: On 7 MHz a dipole constructed of salt water: Er = 81, * conductivity 5 S/m, and 0.5" diameter has a free space efficiency of 0.08%. *i.e. with 100 W input the total radiated power = 80 mW. Frank (VE6CB) That looked so bad I had to run an analysis to see for myself. Sure enough, it's that bad. And even with a 0.25 inch diameter column at 146 MHz, the efficiency is only on the order of 1%. A foot and a half of wire vs. a pump, power source, and ferrite transformer? No contest. Roy Lewallen, W7EL I know Dan Tam, the SPAWAR engineer in the video. He's a pretty sharp guy. I hesitate to throw him into the Lions' Den but I will if you let me watch. :-) "Sal" |
"Ionic Liquid" Antenna
On 9/8/2010 1:03 PM, Cecil Moore wrote:
How many free electrons exist in ionized water? -- 73, Cecil, w5dxp.com I had a dream last night, billions of angels dancing on the head of a pin ... it was quite unsettling! Regards, JS |
"Ionic Liquid" Antenna
On 9/8/2010 8:06 PM, Sal M. Onella wrote:
On Sep 7, 12:22 pm, Roy wrote: That looked so bad I had to run an analysis to see for myself. Sure enough, it's that bad. And even with a 0.25 inch diameter column at 146 MHz, the efficiency is only on the order of 1%. A foot and a half of wire vs. a pump, power source, and ferrite transformer? No contest. Roy Lewallen, W7EL I know Dan Tam, the SPAWAR engineer in the video. He's a pretty sharp guy. I hesitate to throw him into the Lions' Den but I will if you let me watch. :-) "Sal" It's a sad comment on the state of this newsgroup that an objective statement of what are believed to be facts is taken as "throwing [the engineer] into the lions' den". It's not my intent at all to impugn the engineer. Surely he's aware of the efficiency of the "antennas" he's creating, so either my (and Frank's) calculations are grossly incorrect or SPAWAR thinks there's a market for such inefficient antennas. It would be educational to know which of these is the case. It was interesting that there was no mention in the video of very low efficiency, but I guess that's to be expected for a promotional piece produced by a marketing department looking for investors. Roy Lewallen, W7EL |
"Ionic Liquid" Antenna
On 9/8/2010 9:35 PM, Roy Lewallen wrote:
... It's a sad comment on the state of this newsgroup that an objective statement of what are believed to be facts is taken as "throwing [the engineer] into the lions' den". It's not my intent at all to impugn the engineer. Surely he's aware of the efficiency of the "antennas" he's creating, so either my (and Frank's) calculations are grossly incorrect or SPAWAR thinks there's a market for such inefficient antennas. It would be educational to know which of these is the case. It was interesting that there was no mention in the video of very low efficiency, but I guess that's to be expected for a promotional piece produced by a marketing department looking for investors. Roy Lewallen, W7EL Gesus! If it walks like a duck, quacks like a duck, swims like a duck, smells like a duck, sounds like a duck ... well, you know that one. Never thought I would hear you say that ... ya' never had a hard time calling a duck a duck before. Regards, JS |
"Ionic Liquid" Antenna
On Wed, 08 Sep 2010 21:35:19 -0700, Roy Lewallen
wrote: so either my (and Frank's) calculations are grossly incorrect or SPAWAR thinks there's a market for such inefficient antennas. The point I caught, and apparently was not modeled, was the discussion of antenna height for any particular band. Albeit, such mention was fleeting, but it sounded suspiciously like half wave, not quarter wave dimensions. Aside from that speculation, power specs for military usage are appropriate for theater operations, not global communications. When I taught UHF/VHF in the Navy, 10% efficiency was considered perfectly acceptable as point-to-point communications was the only expectation and that was rarely as much as 20 miles at best. Experience teaches that even that only takes 100s of milliwatts. 73's Richard Clark, KB7QHC |
"Ionic Liquid" Antenna
On 9/8/2010 10:50 PM, Richard Clark wrote:
On Wed, 08 Sep 2010 21:35:19 -0700, Roy wrote: so either my (and Frank's) calculations are grossly incorrect or SPAWAR thinks there's a market for such inefficient antennas. The point I caught, and apparently was not modeled, was the discussion of antenna height for any particular band. Albeit, such mention was fleeting, but it sounded suspiciously like half wave, not quarter wave dimensions. Aside from that speculation, power specs for military usage are appropriate for theater operations, not global communications. When I taught UHF/VHF in the Navy, 10% efficiency was considered perfectly acceptable as point-to-point communications was the only expectation and that was rarely as much as 20 miles at best. Experience teaches that even that only takes 100s of milliwatts. 73's Richard Clark, KB7QHC That's still an order of magnitude better than what this antenna seems able to do at VHF, although the demonstration clearly showed it to be adequate for working a local repeater with an HT. But what about HF, which the video clearly mentions? Is a fraction of a percent efficiency adequate for typical communication needs? I know that some military HF use is NVIS, for which a vertical antenna is poorly suited to begin with, so that probably wouldn't be an application. Are milliwatts of radiated HF used and useful for theater communications? Roy Lewallen, W7EL |
"Ionic Liquid" Antenna
On 9 sep, 03:21, Roy Lewallen wrote:
On 9/8/2010 10:50 PM, Richard Clark wrote: On Wed, 08 Sep 2010 21:35:19 -0700, Roy wrote: so either my (and Frank's) calculations are grossly incorrect or SPAWAR thinks there's a market for such inefficient antennas. The point I caught, and apparently was not modeled, was the discussion of antenna height for any particular band. *Albeit, such mention was fleeting, but it sounded suspiciously like half wave, not quarter wave dimensions. Aside from that speculation, power specs for military usage are appropriate for theater operations, not global communications. *When I taught UHF/VHF in the Navy, 10% efficiency was considered perfectly acceptable as point-to-point communications was the only expectation and that was rarely as much as 20 miles at best. *Experience teaches that even that only takes 100s of milliwatts. 73's Richard Clark, KB7QHC That's still an order of magnitude better than what this antenna seems able to do at VHF, although the demonstration clearly showed it to be adequate for working a local repeater with an HT. But what about HF, which the video clearly mentions? Is a fraction of a percent efficiency adequate for typical communication needs? I know that some military HF use is NVIS, for which a vertical antenna is poorly suited to begin with, so that probably wouldn't be an application. Are milliwatts of radiated HF used and useful for theater communications? Roy Lewallen, W7EL- Ocultar texto de la cita - - Mostrar texto de la cita - What about if you are a whale? What if you are a firefighter?, you can got a good 160 m portable antenna in your fire engine! Do you remember the pretty nice "Frequency" film with Dennis Quaid as W2QYV, an ideal antenna for him :D Greetings to all - Miguel Ghezzi - LU6ETJ |
"Ionic Liquid" Antenna
On 9/9/2010 7:03 AM, lu6etj wrote:
... What about if you are a whale? What if you are a firefighter?, you can got a good 160 m portable antenna in your fire engine! Do you remember the pretty nice "Frequency" film with Dennis Quaid as W2QYV, an ideal antenna for him :D Greetings to all - Miguel Ghezzi - LU6ETJ ROFLOL! Good sense of humor man! And, you are totally correct, firemen expending BIG tax dollars for a dollar conversation is about right. Regards, JS |
"Ionic Liquid" Antenna
Having dealt with water streams for a while, I wonder how the stream
is measured, because all streams break up into droplets at some point well before they appear to do so. - 'Doc |
"Ionic Liquid" Antenna
On 9/11/2010 7:46 PM, 'Doc wrote:
Having dealt with water streams for a while, I wonder how the stream is measured, because all streams break up into droplets at some point well before they appear to do so. - 'Doc You are absolutely correct. Would be interesting to have real time monitoring of the match, field strength in relation to a standard 1/4 wave and real power delivered to the water stream. I am thinking this is the dummies, dummy load. Or, the dummy load of the century ... could sure use a 5KW ferrite core like he has, just sink the signal into a "barrel of sal****er dummy load" ... would be nice to be have this dis-proven and start discussing why. Who knows, when the stream goes "live" perhaps the feedline "lights up" as a radiator. As someone already pointed out, the repeater makes one highly suspicious. I mean, is he line of sight from the repeater? How far is he from the repeater? Why didn't he just choose direct contact? Etc., etc. He certainly could have supplied us with better. I just might write him and ask him for a new youtube video and different test parameters. Regards, JS |
"Ionic Liquid" Antenna
On Sep 12, 3:13*am, John Smith wrote:
On 9/11/2010 7:46 PM, 'Doc wrote: Having dealt with water streams for a while, I wonder how the stream is measured, because all streams break up into droplets at some point well before they appear to do so. * - 'Doc You are absolutely correct. *Would be interesting to have real time monitoring of the match, field strength in relation to a standard 1/4 wave and real power delivered to the water stream. *I am thinking this is the dummies, dummy load. *Or, the dummy load of the century ... could sure use a 5KW ferrite core like he has, just sink the signal into a "barrel of sal****er dummy load" ... would be nice to be have this dis-proven and start discussing why. Who knows, when the stream goes "live" perhaps the feedline "lights up" as a radiator. *As someone already pointed out, the repeater makes one highly suspicious. I mean, is he line of sight from the repeater? *How far is he from the repeater? *Why didn't he just choose direct contact? * Etc., etc. *He certainly could have supplied us with better. I just might write him and ask him for a new youtube video and different test parameters. Regards, JS yeah, like compare the signal to one of those rubber coated dummy load antennas. |
"Ionic Liquid" Antenna
On 9/12/2010 4:15 AM, K1TTT wrote:
... yeah, like compare the signal to one of those rubber coated dummy load antennas. Frankly, I thought the guy would have shown up by now laughing. Having had a great laugh on us for attempting to take him seriously ... has me wonderin'! Regards, JS |
"Ionic Liquid" Antenna
On 12 sep, 08:57, John Smith wrote:
On 9/12/2010 4:15 AM, K1TTT wrote: ... yeah, like compare the signal to one of those rubber coated dummy load antennas. Frankly, I thought the guy would have shown up by now laughing. *Having had a great laugh on us for attempting to take him seriously ... has me wonderin'! Regards, JS Hello all OK, this probabily is near a joke or hoax, but what about liquid/ionic/ dielectric in general? I have a pair of interesting links about it = http://ieeexplore.ieee.org/xpl/freea...number=1461138 http://xa.yimg.com/kq/groups/1508589...ennas_IEEE.pdf Time ago I had some doubts about the mobility of ions in a liquid to radiate and calculate how much an electron actually moves when the antenna is radiating to use as a starting point. The numbers (if I do not make mistakes) showed me to a current density in the order of 5 A/mm^2, free electrons can take a trip of just one three thousandth mm of copper ion radius, surprising result!, really I did not expect such a small value ..., It showed me that electrons in antenna barely vibrate around their resting place when radiates (I made calculations for a irradiant at 80 m). This favored hypothesis of liquid antenna possibilities because would suffice for the ions (charges) of the liquid vibrate slightly around their points of rest to act as radiators (I do not to solve issues related + ion mass to best "close" my questions). We know sea water an earth EM wave reflections really are reirradiation of EM energy, then, ionic antennas there are real things, are there? However I haven not study the efficience of this process. What do you think about it? Best regards Miguel LU6ETJ |
"Ionic Liquid" Antenna
On Sun, 12 Sep 2010 11:06:32 -0700 (PDT), lu6etj
wrote: http://ieeexplore.ieee.org/xpl/freea...number=1461138 Hi Miguel, Let's see, half the power lost to the antenna: "A simple monopole antenna was constructed and its reflected impedance and radiation efficiency measured for salt solutions of 2 conductivities and 2 monopole diameters. Two antennas were constructed, 25 mm and 50 mm in diameter, with salt solution at 35 ppt and 70 ppt. The resonant frequency was found to be inversely proportional to salt solution column height, with bandwidths of ?1 GHz (-10 dB S11 points) at 1.3 GHz." A quarterwave monopole @1.3GHz would be 5.8cM tall and up to 5cM in diameter? A mylar balloon filled with air (not water) wouldn't lose half the power applied. Voila! Wide band, 3dB gain, lighter, and can be made into any shape. http://xa.yimg.com/kq/groups/1508589...ennas_IEEE.pdf This has been a topic here going back at least 15 years. Time ago I had some doubts about the mobility of ions in a liquid to radiate and calculate how much an electron actually moves when the antenna is radiating to use as a starting point. The numbers (if I do not make mistakes) showed me to a current density in the order of 5 A/mm^2, free electrons can take a trip of just one three thousandth mm of copper ion radius, surprising result!, really I did not expect such a small value ..., It showed me that electrons in antenna barely vibrate around their resting place when radiates (I made calculations for a irradiant at 80 m). This favored hypothesis of liquid antenna possibilities because would suffice for the ions (charges) of the liquid vibrate slightly around their points of rest to act as radiators (I do not to solve issues related + ion mass to best "close" my questions). Consider a dielectric lens antenna. How much mobility there? We know sea water an earth EM wave reflections really are reirradiation of EM energy, This reflection is a function of a severe mismatch between two poor conductors. You don't need sea water to achieve the same thing. What do you think about it? Consult the authority on invention: http://www.rubegoldberg.com/ 73's Richard Clark, KB7QHC |
"Ionic Liquid" Antenna
On 12 sep, 15:49, Richard Clark wrote:
On Sun, 12 Sep 2010 11:06:32 -0700 (PDT), lu6etj wrote: http://ieeexplore.ieee.org/xpl/freea...number=1461138 Hi Miguel, Let's see, half the power lost to the antenna: * *"A simple monopole antenna was constructed and its reflected * *impedance and radiation efficiency measured for salt solutions * *of 2 conductivities and 2 monopole diameters. Two antennas * *were constructed, 25 mm and 50 mm in diameter, with salt solution * *at 35 ppt and 70 ppt. The resonant frequency was found to * *be inversely proportional to salt solution column height, * *with bandwidths of ?1 GHz (-10 dB S11 points) at 1.3 GHz." A quarterwave monopole @1.3GHz would be 5.8cM tall and up to 5cM in diameter? *A mylar balloon filled with air (not water) wouldn't lose half the power applied. *Voila! *Wide band, 3dB gain, lighter, and can be made into any shape. http://xa.yimg.com/kq/groups/1508589...rees_Antennas_... This has been a topic here going back at least 15 years. Time ago I had some doubts about the mobility of ions in a liquid to radiate and calculate how much an electron actually moves when the antenna is radiating to use as a starting point. The numbers (if I do not make mistakes) showed me to a current density in the order of 5 A/mm^2, free electrons can take a trip of just one three thousandth mm of copper ion radius, surprising result!, really I did not expect such a small value ..., It showed me that electrons in antenna barely vibrate around their resting place when radiates (I made calculations for a irradiant at 80 m). This favored hypothesis of liquid antenna possibilities because would suffice for the ions (charges) of the liquid vibrate slightly around their points of rest to act as radiators (I do not to solve issues related + ion mass to best "close" my questions). Consider a dielectric lens antenna. *How much mobility there? We know sea water an earth EM wave reflections really are reirradiation of EM energy, This reflection is a function of a severe mismatch between two poor conductors. *You don't need sea water to achieve the same thing. What do you think about it? Consult the authority on invention:http://www.rubegoldberg.com/ 73's Richard Clark, KB7QHC Hello dear Richard, how are you? I hope very well with yours: Mylar conductive ballon replacement it is not a valid refutation for the hipotesis analized, that antenna was only a "test antenna", any liquid antenna can be replaced by a metalic antenna...! what prove that? I was not be here fifty year ago :) (I suppose "ether" also must have been treated in this newsgropup a hundred years ago :D ) what you think about it (trees) at that time? I do not know lens dielectric antennas, I learnt radiation it due accelerating charges, electrons are charges, free ions also, non free dielectric charges (E field induced dipoles) too; alternating electric field applied to them produce movement on them, then acceleration, then = radiation. Am I wrong? (yes I know, loss too sometimes). You say: "This reflection is a function of a severe mismatch between two poor conductors. You don't need sea water to achieve the same thing" What "two" conductors? you know air not work as a "conductor" in this analitic environment, it would the same it there were empty vacuum, reflecting medium properties are responsibles for earth reflections. "Mismatch" it is another magic word, improper of you indeed my friend!, not an explanation :) Classic EM radiation (or the same "re-irradiation") it sometimes explained due accelarating charges, and YES, I agree with you, certainly "you do not need sea water to achieve the same thing", you can do it with any other vibrating charge, sea water charges it is only one possibility, conductors, soil substances are other familiar things capable to do it. We know waves are reflected to ionosphere by those mediums, we can explain that reflections with incident electromagnetic fields and earth surface induced currents; however, "current" not implies here free electrons traveling miles inside a conductor, we have a "current" with any little induced movement on a charge and if this movemente is not constant we have acceleration then = EM radiation, what other classical process could explain the EM earth reflection? I do not know. However I am not supporting practical liquid antennas here, I have not made the experience and I have not theoretical enough knowledge neither to prove or refute the hipotesis without much more working, I only have some pointers to think over about it. 73 Miguel LU6ETJ |
"Ionic Liquid" Antenna
On Sun, 12 Sep 2010 15:30:04 -0700 (PDT), lu6etj
wrote: Hello dear Richard, how are you? I hope very well with yours: Mylar conductive ballon replacement it is not a valid refutation for the hipotesis analized, that antenna was only a "test antenna", any liquid antenna can be replaced by a metalic antenna...! what prove that? Hi Miguel, What does it prove? What does water prove? That it is a poor replacement? Yes. I do not know lens dielectric antennas, I learnt radiation it due accelerating charges, That repeated epithet is rather too simple. An electron is always accelerating. A circular orbit guarantees that. electrons are charges, free ions also, non free dielectric charges (E field induced dipoles) too; alternating electric field applied to them produce movement on them, then acceleration, then = radiation. Am I wrong? (yes I know, loss too sometimes). Does swinging a battery around produce radiation? You say: "This reflection is a function of a severe mismatch between two poor conductors. You don't need sea water to achieve the same thing" What "two" conductors? POOR conductors. you know air not work as a "conductor" in this analitic environment, Right, it is a very poor conductor (and, yet, we still see lightning conducting through it on a summer evening - all a matter of degree). it would the same it there were empty vacuum, reflecting medium properties are responsibles for earth reflections. I suppose so. "Mismatch" it is another magic word, improper of you indeed my friend!, not an explanation :) Magic happens. Classic EM radiation (or the same "re-irradiation") it sometimes explained due accelarating charges, and YES, I agree with you, certainly "you do not need sea water to achieve the same thing", you can do it with any other vibrating charge, sea water charges it is only one possibility, conductors, soil substances are other familiar things capable to do it. So then, classic EM radiation is pretty common, and has lost its magic. We know waves are reflected to ionosphere by those mediums, we can explain that reflections with incident electromagnetic fields and earth surface induced currents; however, "current" not implies here free electrons traveling miles inside a conductor, we have a "current" with any little induced movement on a charge and if this movemente is not constant we have acceleration then = EM radiation, what other classical process could explain the EM earth reflection? I do not know. Mismatch. However I am not supporting practical liquid antennas here, I have not made the experience and I have not theoretical enough knowledge neither to prove or refute the hipotesis without much more working, I only have some pointers to think over about it. Ever hear a flame speaker? No magnets, no cone, just a flame and an amplifier feeding two probes and *sound* comes out. No one builds them either. 73's Richard Clark, KB7QHC |
"Ionic Liquid" Antenna
On 12 sep, 22:17, Richard Clark wrote:
On Sun, 12 Sep 2010 15:30:04 -0700 (PDT), lu6etj wrote: Hello dear Richard, how are you? I hope very well with yours: Mylar conductive ballon replacement it is not a valid refutation for the hipotesis analized, that antenna was only a "test antenna", any liquid antenna can be replaced by a metalic antenna...! what prove that? Hi Miguel, What does it prove? *What does water prove? *That it is a poor replacement? *Yes. I do not know lens dielectric antennas, I learnt radiation it due accelerating charges, That repeated epithet is rather too simple. *An electron is always accelerating. *A circular orbit guarantees that. electrons are charges, free ions also, non free dielectric charges (E field induced dipoles) too; alternating electric field applied to them produce movement on them, then acceleration, then = radiation. Am I wrong? (yes I know, loss too sometimes). Does swinging a battery around produce radiation? You say: "This reflection is a function of a severe mismatch between two poor conductors. *You don't need sea water to achieve the same thing" What "two" conductors? POOR conductors. you know air not work as a "conductor" in this analitic environment, Right, it is a very poor conductor (and, yet, we still see lightning conducting through it on a summer evening - all a matter of degree). it would the same it there were empty vacuum, reflecting medium properties are responsibles for earth reflections. I suppose so. "Mismatch" it is another magic word, improper of you indeed my friend!, not an explanation :) Magic happens. Classic EM radiation (or the same "re-irradiation") it sometimes explained due accelarating charges, and YES, I agree with you, certainly "you do not need sea water to achieve the same thing", you can do it with any other vibrating charge, sea water charges it is only one possibility, conductors, soil substances are other familiar things capable to do it. So then, classic EM radiation is pretty common, and has lost its magic. We know waves are reflected to ionosphere by those mediums, we can explain that reflections with incident electromagnetic fields and earth surface induced currents; however, "current" not implies here free electrons traveling miles inside a conductor, we have a "current" with any little induced movement on a charge and if this movemente is not constant we have acceleration then = EM radiation, what other classical process could explain the EM earth reflection? I do not know. Mismatch. However I am not supporting practical liquid antennas here, I have not made the experience and I have not theoretical enough knowledge neither to prove or refute the hipotesis without much more working, I only have some pointers to think over about it. Ever hear a flame speaker? *No magnets, no cone, just a flame and an amplifier feeding two probes and *sound* comes out. *No one builds them either. 73's Richard Clark, KB7QHC How easy it is for you, eh? some day I will catch you in spanish... :) Well, it is funny discuss some things with you. (Sorry, I don know how properly quoting with Google, let me use for your sentences). ......... Is not that IEEE paper what you called "the Workbench", have done your duties in "The Bench" to refute that paper? :D ...... What does it prove? What does water prove? That it is a poor replacement? Yes Certainly "a wooden leg it is a poor replacement for the original one" (Capt. Hooke dixit), but it is better than no leg at all when you do not have money to pay "the million dollar man leg". Science deals with possibilities not with Harvard economists efficientist laws. We, carbonous beings have made of electrolites, open your ham mind, what was about spirit of "to boldly go where no man has gone before"? ........ That repeated epithet is rather too simple. An electron is always accelerating. A circular orbit guarantees that. Time ago you have troubles with this item, until today do you not believes Bohr postulates was intended for atomic orbitals?, do you have forgotten ciclotron radiation?, I talked to you about this curious habit of emmiting waves of circular accelerated charges when we are young. ........ Does swinging a battery around produce radiation? Do you believe? ....... Air a POOR conductor of EM? Oh no! you are not my Clarke, this newsgroup has been infiltered by etherians. They have hi jacked my old newsgroup friend...! (electronic ether, where I read that, before?) ...... PSE explain me MISMATCH. (I bet that "mismatch" in some point will ends up in Maxwell's Faraday and generalized Ampere law). 73 (so much english for a day to me) Miguel Ghezzi |
"Ionic Liquid" Antenna
"lu6etj" wrote ... ....... Air a POOR conductor of EM? Oh no! you are not my Clarke, this newsgroup has been infiltered by etherians. They have hi jacked my old newsgroup friend...! (electronic ether, where I read that, before?) Now everywhere is the plazma ether. Even in the seewater: http://users.cecs.anu.edu.au/~trumpf...rmittivity.pdf S* |
"Ionic Liquid" Antenna
On Sun, 12 Sep 2010 22:46:16 -0700 (PDT), lu6etj
wrote: PSE explain me MISMATCH. What is the characteristic Z of free space or air? What is the characteristic Z of Water (plain, with mud, or salty)? What is the ratio between the two? How much power in one, transits the interface and proceeds through the other? [hint] if not much, it is reflected at the interface. 73's Richard Clark, KB7QHC |
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