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Hi, ? FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests. ? In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not: ? 3.750 MHz ~ 1.0-1.1 SWR 7.010 MHz ~ 1.1-1.2 SWR 14.200~250 MHz – 1.3 SWR … 28 MHz – 1.2x SWR ? These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now. ? Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length. ? We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design. ? 73 de N3RDX Washington, DC
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Can you ship a picture or drawing. Would help to visualize. Also forwarded to another group of smarter hams.?
W4DBL?
Doug Lynch
President?
Aries International, LLC
?
D: +1-321-415-2191
M:?+1-478-318-2655
?
E: Doug@...?
Port Orange, FL
toggle quoted message
Show quoted text
On Feb 19, 2023, at 21:39, Samudra via groups.io <samudra.haque@...> wrote:
?
Hi,
?
FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was
left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for
regional contacts to try scheduled tests.
?
In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication
will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not:
?
3.750 MHz ~ 1.0-1.1 SWR
7.010 MHz ~ 1.1-1.2 SWR
14.200~250 MHz – 1.3 SWR
…
28 MHz – 1.2x SWR
?
These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the
lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now.
?
Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from
antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length.
?
We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability
and repeatability with the complex measurements mechanical and electrical per the design.
?
73 de N3RDX
Washington, DC
|
What general type of antenna is it?
Joe n1khb
On Sun, Feb 19, 2023 at 9:39 PM, Samudra <samudra.haque@...> wrote: Hi, ? FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests. ? In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not: ? 3.750 MHz ~ 1.0-1.1 SWR 7.010 MHz ~ 1.1-1.2 SWR 14.200~250 MHz – 1.3 SWR … 28 MHz – 1.2x SWR ? These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now. ? Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length. ? We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design. ? 73 de N3RDX Washington, DC
|
Apparently it's a type of vertical (1' x 1' x 12').
Is there a reason to think this design is not included in the ARRL publications of the era Ken, N2VIP
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Show quoted text
On Feb 19, 2023, at 21:45, Joseph Wonoski via groups.io <N1KHB@...> wrote:
?What general type of antenna is it?
Joe n1khb
On Sun, Feb 19, 2023 at 9:39 PM, Samudra <samudra.haque@...> wrote: Hi, ? FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests. ? In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not: ? 3.750 MHz ~ 1.0-1.1 SWR 7.010 MHz ~ 1.1-1.2 SWR 14.200~250 MHz – 1.3 SWR … 28 MHz – 1.2x SWR ? These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now. ? Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length. ? We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design. ? 73 de N3RDX Washington, DC
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No no, not a vertical. Horizontal orientation models only. There wasn't a name for this antenna in a 1958 article by? M. J. Heavyside, Ph.D (G2QM) he published theory and a report of his work.
So, others called it a variety of names. I wrote to UK hams abiut two years ago who sourced the article for me from their archives.??
N2VIP Which ARRL era publication would have published this??
So far the most apt name I have used in my modeling is non-inductive end-loaded antenna (NEDA)? comprising radiating and non-radatinv regions. Selecting 80m to 10m coverage I got 1ft H X 1ft w X 12ft L.?
L is horizontal dimension, total length.?
We made a third version of this system with a poly fabric embedded with antenna elements ... total dimensions 12ft L x 2.5ft W x 1 inch. It did work, better than others, but the wind blew the damn antenna post tripod over as we had created a sail that twists and turns with gusts. Well we have a lot of engineering to do on that one.?
Sorry I don't have any nice pictures to distribute as we are just experimenting with materials and all of our tests are cheaply made up of home depot products. The measurements are somewhat different between prototypes as we discover the cost of the parts we have to fabricate and make durable for long term outside use. It's should be a mature design for showing in a few months.?
73 de X
On Sun, Feb 19, 2023, 22:51 Ken N2VIP < ken@...> wrote: Apparently it's a type of vertical (1' x 1' x 12').
Is there a reason to think this design is not included in the ARRL publications of the era Ken, N2VIP ?What general type of antenna is it?
Joe n1khb
On Sun, Feb 19, 2023 at 9:39 PM, Samudra Hi, ? FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests. ? In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not: ? 3.750 MHz ~ 1.0-1.1 SWR 7.010 MHz ~ 1.1-1.2 SWR 14.200~250 MHz – 1.3 SWR … 28 MHz – 1.2x SWR ? These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now. ? Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length. ? We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design. ? 73 de N3RDX Washington, DC
|
Correction:
NEDA = non-inductive end loaded dipole antenna.?
That's pretty much the theory of the system I can figure out. I wrote GNU octave code to produce geometry and then did antenna analysis on the geometry.?
No no, not a vertical. Horizontal orientation models only. There wasn't a name for this antenna in a 1958 article by? M. J. Heavyside, Ph.D (G2QM) he published theory and a report of his work.
So, others called it a variety of names. I wrote to UK hams abiut two years ago who sourced the article for me from their archives.??
N2VIP Which ARRL era publication would have published this??
So far the most apt name I have used in my modeling is non-inductive end-loaded antenna (NEDA)? comprising radiating and non-radatinv regions. Selecting 80m to 10m coverage I got 1ft H X 1ft w X 12ft L.?
L is horizontal dimension, total length.?
We made a third version of this system with a poly fabric embedded with antenna elements ... total dimensions 12ft L x 2.5ft W x 1 inch. It did work, better than others, but the wind blew the damn antenna post tripod over as we had created a sail that twists and turns with gusts. Well we have a lot of engineering to do on that one.?
Sorry I don't have any nice pictures to distribute as we are just experimenting with materials and all of our tests are cheaply made up of home depot products. The measurements are somewhat different between prototypes as we discover the cost of the parts we have to fabricate and make durable for long term outside use. It's should be a mature design for showing in a few months.?
73 de X On Sun, Feb 19, 2023, 22:51 Ken N2VIP < ken@...> wrote: Apparently it's a type of vertical (1' x 1' x 12').
Is there a reason to think this design is not included in the ARRL publications of the era Ken, N2VIP ?What general type of antenna is it?
Joe n1khb
On Sun, Feb 19, 2023 at 9:39 PM, Samudra Hi, ? FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests. ? In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not: ? 3.750 MHz ~ 1.0-1.1 SWR 7.010 MHz ~ 1.1-1.2 SWR 14.200~250 MHz – 1.3 SWR … 28 MHz – 1.2x SWR ? These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now. ? Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length. ? We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design. ? 73 de N3RDX Washington, DC
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Very interesting. I have a small space for the antennas and up to now I never had something for 80m.
How can we understand if we can build it with the equipment we have?
Pietro I2OIM
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It appears to be mentioned in this amusing radio club newsletter from 1963:
Apparently a version of it enabling an operator in Bradford to cause interference in Denmark using only 9w on top band from a loft-installed antenna!
Would be nice to see a copy of the original "Aerials for Confined Spaces" - RSGB - but doesn't appear to exist on the web.. Maybe a visit to a library is required?
73
James M0JMX
On Mon, Feb 20, 2023 at 9:18 AM Pietro Molina < pietro@...> wrote: Very interesting. I have a small space for the antennas and up to now I never had something for 80m.
How can we understand if we can build it with the equipment we have?
Pietro I2OIM
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It sure sounds like this:
The date of the article is probably around 2003, given the comment here:
In the 70's and 80's my crowd played around a lot with metal tape on plastic sheet antennas, mostly VHF yagis. Mechanical challenges were often challenging.
We tried a few fractal HF antennas, too:
interest and experimentation is novel HF designs seems to roughly correspond with sunspots, and since n5ese's work was at a time when solar activity is about what it is now (pretty good), I think its probably a good time to experiment with one of these, if you're so inclined.
73, have fun! Jeff kn8a
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On Mon, Feb 20, 2023 at 06:28 AM, Jeff wrote:
Mechanical challenges were often challenging.
Not enough coffee yet...
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Thanks James M0JMX, the original article (1950s) is what I used to model practical antennas that can be made from now on. There were couple of versions, possibly a technical paper as well but I didnt have resources to locate those from the original institutions.?
It appears to be mentioned in this amusing radio club newsletter from 1963:
Apparently a version of it enabling an operator in Bradford to cause interference in Denmark using only 9w on top band from a loft-installed antenna!
Would be nice to see a copy of the original "Aerials for Confined Spaces" - RSGB - but doesn't appear to exist on the web.. Maybe a visit to a library is required?
73
James M0JMX
On Mon, Feb 20, 2023 at 9:18 AM Pietro Molina < pietro@...> wrote: Very interesting. I have a small space for the antennas and up to now I never had something for 80m.
How can we understand if we can build it with the equipment we have?
Pietro I2OIM
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Jeff K8NA, It took about a year of design, several jigs and a two & three person effort to get the assembly working as the elements needed stringing with wires that always sagged until we came up with braces and fashioned a set of custom fasteners amd supports. Out goal was to make it transportable... for you know field day, shipping and storage.?
The mechanical SME and ham cursed me many times at changing requirements of course. This is a very difficult design not really suited for homebrew one offs IMHO.?
It sure sounds like this:
The date of the article is probably around 2003, given the comment here:
In the 70's and 80's my crowd played around a lot with metal tape on plastic sheet antennas, mostly VHF yagis.? Mechanical challenges were often challenging.
We tried a few fractal HF antennas, too:
interest and experimentation is novel HF designs seems to roughly correspond with sunspots, and since n5ese's work was at a time when solar activity is about what it is now (pretty good),? I think its probably a good time to experiment with one of these, if you're so inclined.
73, have fun! Jeff kn8a
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Sam
The antenna does work. I struggled with keeping it all in line at times.
I tried a couple of ideas with a few different prototypes in my practical experiments
I may have it somewhere still
John VE3IPS -- John VE3IPS Radio is a Lifestyle not a Hobby Oprah added the ARRL Handbook to her list
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"N2VIP Which ARRL era publication would have published this?"
You said hams were discussing this antenna design for three decades,?
"a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s."
Are you telling me it was such a hot topic that it was discussed for 3 decades yet it never got written up for the Handbook, Antenna book, or QST? Ken, N2VIP On Feb 19, 2023, at 23:16, Samudra <samudra.haque@...> wrote:
? No no, not a vertical. Horizontal orientation models only. There wasn't a name for this antenna in a 1958 article by? M. J. Heavyside, Ph.D (G2QM) he published theory and a report of his work.
So, others called it a variety of names. I wrote to UK hams abiut two years ago who sourced the article for me from their archives.??
N2VIP Which ARRL era publication would have published this??
So far the most apt name I have used in my modeling is non-inductive end-loaded antenna (NEDA)? comprising radiating and non-radatinv regions. Selecting 80m to 10m coverage I got 1ft H X 1ft w X 12ft L.?
L is horizontal dimension, total length.?
We made a third version of this system with a poly fabric embedded with antenna elements ... total dimensions 12ft L x 2.5ft W x 1 inch. It did work, better than others, but the wind blew the damn antenna post tripod over as we had created a sail that twists and turns with gusts. Well we have a lot of engineering to do on that one.?
Sorry I don't have any nice pictures to distribute as we are just experimenting with materials and all of our tests are cheaply made up of home depot products. The measurements are somewhat different between prototypes as we discover the cost of the parts we have to fabricate and make durable for long term outside use. It's should be a mature design for showing in a few months.?
73 de X
<snip>
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N2VIP, not sure if you have read the other comments (Jeff KN8A & James M0JMX)???in this thread.?
I didn't claim to know either way (yes/no) if any ARRL (or any other US predecessor) publication covered this innovative antenna treatment, that I know from my fact finding was published in 1958, but I found references to earlier documents - and quote from the researcher/author that he is describing methods/practices used in WW2. I am yet to find any scholar article that outlines the theory by which this antenna system works, but of the various antenna analyzer programs I used, only 1 was able to calculate its lobes due to the "folding" requirements.?
I have asked senior?EEE and RF SME on this antenna, and they have a wealth?of design expertise in all things RF, Antenna for US branches and industries - and they all came up with exactly 0.00 knowledge on this design. In fact they contributed to studying it and doing their own Matlab models and for people who have dealt with sub-mm Wave EM analysis from VHF, one would think they know their stuff over 50 years.?
However I do know from my own personal background in South Asia, (I was S21X) the practice of "folding" HF antennas is common for military people?who deal with HF communications using backpack radios - just as Dr. Heavyside wrote. That's why - when I came across the article, searching for ham radio antennas for confined spaces - and I must stay some authors mentioned examples of such a mythical antenna in publications but never actually described it - I read it and visualized in my mind the first real military set (1970s at a military exhibition) I had a chance to ask about that had indeed a folded antenna. It did not have any inductors, or capacitive hats just flat flexible whips.
Now, since you believe there should be US coverage, if you could explain yourself where I missed such a mention in any of the ARRL (or any other US) handbooks I have seen from the 1970s onwards - that would be welcome addition to the knowledge bank.
On Mon, Feb 20, 2023 at 11:06 AM Ken N2VIP < ken@...> wrote: "N2VIP Which ARRL era publication would have published this?"
You said hams were discussing this antenna design for three decades,?
"a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s."
Are you telling me it was such a hot topic that it was discussed for 3 decades yet it never got written up for the Handbook, Antenna book, or QST? Ken, N2VIP ? No no, not a vertical. Horizontal orientation models only. There wasn't a name for this antenna in a 1958 article by? M. J. Heavyside, Ph.D (G2QM) he published theory and a report of his work.
So, others called it a variety of names. I wrote to UK hams abiut two years ago who sourced the article for me from their archives.??
N2VIP Which ARRL era publication would have published this??
So far the most apt name I have used in my modeling is non-inductive end-loaded antenna (NEDA)? comprising radiating and non-radatinv regions. Selecting 80m to 10m coverage I got 1ft H X 1ft w X 12ft L.?
L is horizontal dimension, total length.?
We made a third version of this system with a poly fabric embedded with antenna elements ... total dimensions 12ft L x 2.5ft W x 1 inch. It did work, better than others, but the wind blew the damn antenna post tripod over as we had created a sail that twists and turns with gusts. Well we have a lot of engineering to do on that one.?
Sorry I don't have any nice pictures to distribute as we are just experimenting with materials and all of our tests are cheaply made up of home depot products. The measurements are somewhat different between prototypes as we discover the cost of the parts we have to fabricate and make durable for long term outside use. It's should be a mature design for showing in a few months.?
73 de X
<snip>
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On Mon, Feb 20, 2023 at 03:28 AM, Jeff wrote:
It sure sounds like this:
Looks like a "meander line" antenna. Not uncommon to see an entire antenna done this way on 433MHz and up radio modules. I swear, every 2.4GHz transceiver module must use the meander line antenna. ? -- Steven J Greenfield AE7HD
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yes, finally ! well, almost.?
On a PCB meander line antenna?the radiation resistance equation gets complicated due to PCB dielectric and also co-planar?and planar conductive surfaces (other traces that could possibly exhibit RF coupling with the main antenna) and also the semiconductor IC that is producing the RF needs ground plane of some sort, that complicates things as well.. Apparently the "trapezoid" cross sectional shape of the traces also present issues in getting antennas to radiate where they are supposed to.? On Mon, Feb 20, 2023 at 11:26 AM Steven Greenfield AE7HD via <alienrelics= [email protected]> wrote:
On Mon, Feb 20, 2023 at 03:28 AM, Jeff wrote:
It sure sounds like this:
Looks like a "meander line" antenna. Not uncommon to see an entire antenna done this way on 433MHz and up radio modules. I swear, every 2.4GHz transceiver module must use the meander line antenna.
?
--
Steven J Greenfield AE7HD
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A headline such as? "Results of new US antenna design" is somewhat disappointing when all references in this thread indicate it's a revisit of published material from 50 years ago.
SWR is NOT --IS NOT an indicator as to how well an antenna performs..
Performance is relative. and comparisons are generally made against a dipole or unity gain antenna. Isotropic is an imaginary radiator by the way.?
as stated in this URL :
Performance or efficiency of shortened antennas can be calculated and you may find an antenna such as the subject may only be 2-55% efficient.
and that's compared to a dipole which is only maximum 98% efficient- Because NO electronic component is 100% efficient.
98% is a relatively acceptable figure, however when we're talking 2% to 25%, no this is a factor that should concern most. Yet convenience, ease of erection? (not that -you dirty minded)? may dictate 10% antenna efficiencies acceptable for the purpose intended.?
I'd rather crank down the power output of my 100 watt rig to 10 watts, than to run 100 watts into a 10% efficient antenna. To radiate 10 watts.
The "boast" to be able to work Kansas to North Carolina or NY to Ireland on 5 watts is hollow, capricious and arbitrary as factors such as propagation, the other stations antenna, what band, what mode and so on, makes that a crap shoot. One that newbie hams jump at the sales pitch of that magic silver bullet $25 revolutionary antenna, and buys into it. Like the current (pun intended) Balun requirement.. Yet look a the ARRL Antenna Handbook. Not a single dipole project includes or demands a balun. Pure Wives tale bunk. The only gain with a Balun is the Balun salesman's pocketbook. A Balun is only needed for impedance matching AND it's use reduces efficiencies, as? AGAIN no electronic component is 100% efficient.
When I lived in the Boston Area I attended some lectures of groups from? MIT & Harvard regarding "Fractal antennas" and everyone was jumping on the boat. Why, the military was interested and that meant money to many companies that could not sell $600 toilet seats to the government as that deal was locked down by someone else. Would you pay $600 for your toilet seat, NO ---but the government does..
I'm tired of seeing today's newbies buying $98 40 meter dipoles and feeding it with $1.89 per foot coax. to install it in their back yard at 22 feet. Then think they have a good antenna. Yet a year later they are looking to buy an Amplifier? because they come to the realization that they need more power to compete. Not that their antenna is inadequate. Success is having the right combination of components.
Solid antenna theory and design was accomplished 100 years ago. Even a 1954 ARRL Antenna Handbook has a wealth of valid information, the newbie of today ignores. Facebook is the new Antenna Expert source.. NOT!
Regards to those in agreement,
Larry W8LM
ARRL Life member -licensed 57 years.
?
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W8LM,?
Instead of the word "new" what would you you consider acceptable?? Technology is reinvented and adapted everyday. What we are developing is practical functional examples of the original description which obviously came with no parts list or instructions.??
You wrote you know a lot, and it's obvious. Perhaps you could also acknowledge it's in the nature of the amateur radio service to experiment and improve, and to report results of any effort to get advice from others.??
I don't see why you would choose to lecture on the "inadequate" treatment we are pursuing when you actually can't get a functional copy from a retailer of this "old" design anywhere - not for lack of trying, and not for the lack of efforts by others before us.?
At the very least you are a? mature and experienced OM and could have asked me to get working on presenting the RF analysis using VNA and other tools at an upcoming forum somewhere so ... I guess the knowledge can be transferred to others?
Or would you then continue to complain loudly in long diatribes that my team and I have no academic qualifications to do so, in your estimation. I offer my apologies in this letter if that wasn't your intention, but if you read your own words from an outside perspective that is what it sounds like.?
(BTW, my own father was an accomplished academic who refused to write any of his 65 books on art, history and archeology in any manner that we could reprint for wide publication. And now a year after his death, the foundation he setup with my mother (also historian who wanted to publish a lot) is deluged with requests for copies of those textbooks which earlier generation of scholars could never ever afford and get printed access to. I am funding that effort now, and will ensure his work from 70s gets to the community asking for it finally after 15 years. )
Is it not a common complaint that US ham radio has turned into a very limited hobby? Are we increasing numbers of operators and diversity like other countries are able to do?
That's why I spent my time to make something "new" and not worry about how different it is from what has been done before.?
73 de N3RDX/S21X
On Mon, Feb 20, 2023, 12:02 Larry Macionski via <am_fm_radio= [email protected]> wrote: A headline such as? "Results of new US antenna design" is somewhat disappointing when all references in this thread indicate it's a revisit of published material from 50 years ago.
SWR is NOT --IS NOT an indicator as to how well an antenna performs..
Performance is relative. and comparisons are generally made against a dipole or unity gain antenna. Isotropic is an imaginary radiator by the way.?
as stated in this URL :
Performance or efficiency of shortened antennas can be calculated and you may find an antenna such as the subject may only be 2-55% efficient.
and that's compared to a dipole which is only maximum 98% efficient- Because NO electronic component is 100% efficient.
98% is a relatively acceptable figure, however when we're talking 2% to 25%, no this is a factor that should concern most. Yet convenience, ease of erection? (not that -you dirty minded)? may dictate 10% antenna efficiencies acceptable for the purpose intended.?
I'd rather crank down the power output of my 100 watt rig to 10 watts, than to run 100 watts into a 10% efficient antenna. To radiate 10 watts.
The "boast" to be able to work Kansas to North Carolina or NY to Ireland on 5 watts is hollow, capricious and arbitrary as factors such as propagation, the other stations antenna, what band, what mode and so on, makes that a crap shoot. One that newbie hams jump at the sales pitch of that magic silver bullet $25 revolutionary antenna, and buys into it. Like the current (pun intended) Balun requirement.. Yet look a the ARRL Antenna Handbook. Not a single dipole project includes or demands a balun. Pure Wives tale bunk. The only gain with a Balun is the Balun salesman's pocketbook. A Balun is only needed for impedance matching AND it's use reduces efficiencies, as? AGAIN no electronic component is 100% efficient.
When I lived in the Boston Area I attended some lectures of groups from? MIT & Harvard regarding "Fractal antennas" and everyone was jumping on the boat. Why, the military was interested and that meant money to many companies that could not sell $600 toilet seats to the government as that deal was locked down by someone else. Would you pay $600 for your toilet seat, NO ---but the government does..
I'm tired of seeing today's newbies buying $98 40 meter dipoles and feeding it with $1.89 per foot coax. to install it in their back yard at 22 feet. Then think they have a good antenna. Yet a year later they are looking to buy an Amplifier? because they come to the realization that they need more power to compete. Not that their antenna is inadequate. Success is having the right combination of components.
Solid antenna theory and design was accomplished 100 years ago. Even a 1954 ARRL Antenna Handbook has a wealth of valid information, the newbie of today ignores. Facebook is the new Antenna Expert source.. NOT!
Regards to those in agreement,
Larry W8LM
ARRL Life member -licensed 57 years.
?
|
Not sure if this antenna is one I had seen years ago for AM broadcast.? Was made by European group, but when FCC required them to field test in US to get approval for AM broadcast, the group claimed it got damaged in shipment and could not test, sure.
The AM broadcast version is large, but much smaller than other AM broadcast antennas.
Yes would like to see a diagram of it.? One can make all kinds of claims for antennas, but have seen some good work done on antennas and always open to what others have done.
73, ron, n9ee/r Ron Wright, N9EE/R Hernando Co ARES EC
Spring Hill, Florida also n9ee55@...
On Monday, February 20, 2023 at 12:35:23 PM EST, Samudra <samudra.haque@...> wrote:
W8LM,?
Instead of the word "new" what would you you consider acceptable?? Technology is reinvented and adapted everyday. What we are developing is practical functional examples of the original description which obviously came with no parts list or instructions.??
You wrote you know a lot, and it's obvious. Perhaps you could also acknowledge it's in the nature of the amateur radio service to experiment and improve, and to report results of any effort to get advice from others.??
I don't see why you would choose to lecture on the "inadequate" treatment we are pursuing when you actually can't get a functional copy from a retailer of this "old" design anywhere - not for lack of trying, and not for the lack of efforts by others before us.?
At the very least you are a? mature and experienced OM and could have asked me to get working on presenting the RF analysis using VNA and other tools at an upcoming forum somewhere so ... I guess the knowledge can be transferred to others?
Or would you then continue to complain loudly in long diatribes that my team and I have no academic qualifications to do so, in your estimation. I offer my apologies in this letter if that wasn't your intention, but if you read your own words from an outside perspective that is what it sounds like.?
(BTW, my own father was an accomplished academic who refused to write any of his 65 books on art, history and archeology in any manner that we could reprint for wide publication. And now a year after his death, the foundation he setup with my mother (also historian who wanted to publish a lot) is deluged with requests for copies of those textbooks which earlier generation of scholars could never ever afford and get printed access to. I am funding that effort now, and will ensure his work from 70s gets to the community asking for it finally after 15 years. )
Is it not a common complaint that US ham radio has turned into a very limited hobby? Are we increasing numbers of operators and diversity like other countries are able to do?
That's why I spent my time to make something "new" and not worry about how different it is from what has been done before.?
73 de N3RDX/S21X
On Mon, Feb 20, 2023, 12:02 Larry Macionski via <am_fm_radio= [email protected]> wrote: A headline such as? "Results of new US antenna design" is somewhat disappointing when all references in this thread indicate it's a revisit of published material from 50 years ago.
SWR is NOT --IS NOT an indicator as to how well an antenna performs..
Performance is relative. and comparisons are generally made against a dipole or unity gain antenna. Isotropic is an imaginary radiator by the way.?
as stated in this URL :
Performance or efficiency of shortened antennas can be calculated and you may find an antenna such as the subject may only be 2-55% efficient.
and that's compared to a dipole which is only maximum 98% efficient- Because NO electronic component is 100% efficient.
98% is a relatively acceptable figure, however when we're talking 2% to 25%, no this is a factor that should concern most. Yet convenience, ease of erection? (not that -you dirty minded)? may dictate 10% antenna efficiencies acceptable for the purpose intended.?
I'd rather crank down the power output of my 100 watt rig to 10 watts, than to run 100 watts into a 10% efficient antenna. To radiate 10 watts.
The "boast" to be able to work Kansas to North Carolina or NY to Ireland on 5 watts is hollow, capricious and arbitrary as factors such as propagation, the other stations antenna, what band, what mode and so on, makes that a crap shoot. One that newbie hams jump at the sales pitch of that magic silver bullet $25 revolutionary antenna, and buys into it. Like the current (pun intended) Balun requirement.. Yet look a the ARRL Antenna Handbook. Not a single dipole project includes or demands a balun. Pure Wives tale bunk. The only gain with a Balun is the Balun salesman's pocketbook. A Balun is only needed for impedance matching AND it's use reduces efficiencies, as? AGAIN no electronic component is 100% efficient.
When I lived in the Boston Area I attended some lectures of groups from? MIT & Harvard regarding "Fractal antennas" and everyone was jumping on the boat. Why, the military was interested and that meant money to many companies that could not sell $600 toilet seats to the government as that deal was locked down by someone else. Would you pay $600 for your toilet seat, NO ---but the government does..
I'm tired of seeing today's newbies buying $98 40 meter dipoles and feeding it with $1.89 per foot coax. to install it in their back yard at 22 feet. Then think they have a good antenna. Yet a year later they are looking to buy an Amplifier? because they come to the realization that they need more power to compete. Not that their antenna is inadequate. Success is having the right combination of components.
Solid antenna theory and design was accomplished 100 years ago. Even a 1954 ARRL Antenna Handbook has a wealth of valid information, the newbie of today ignores. Facebook is the new Antenna Expert source.. NOT!
Regards to those in agreement,
Larry W8LM
ARRL Life member -licensed 57 years.
?
|
Doug Lynch NNJ4EM
Pietro Molina
John
Larry Macionski