On Feb 20, 2023, at 19:27, Samudra <samudra.haque@...> wrote:

<snip>

So for an 80m band operation, reducing that to 12feet in total length should put this antenna in a different class than what you described.?

Now if someone can point out? a horizontal dipole with capacity hats design, that would be interesting?to see. But note I defined the length?of the dipole as HWL, so on each side, we have a huge number of feet of antenna wire length.?

You mean like this?

I'm planning to venture into FT8 for the first time, and I'm going to use my FT-817.? I'm looking for a USB interface (w/ sound card), and it looks like the SignaLink SLUSB6PM might be the most popular solution.? Is that the right model # for the '817?? The SignaLink has been around a long time... maybe too long (I'm wondering if there's something newer and better that's in the same price range)??

If you're operating FT8 (or other digital modes) on your FT-817, which interface are you using?
Any suggestions/comments much appreciated.? Thanks much!

Larry, WA2VKG

Guys,
It seems that you have missed exactly what this antenna is.? The cage acts like a capacity hat, adding enough impedance at the ends to bring the antenna to resonance.? I think you may also be mixing terms when talking about efficiency.? It in the above example of tuning the input to a transmission line so that maximum power is delivered into the transmission line does not mean that power is actually radiated.? Lossy parts of the antenna system, ground included, do not radiate.? There are literally thousands of articles on using capacity hats at the ends of radiators to bring the antenna into resonance but the part of the radiation resistance equation that radiates is still very small compared to a full size radiator.? So while you may approach 98% efficiency for the transmitter load, you may not be radiating that power into space.? It is possible for that power to be dissipated in wire losses, or ground losses or even in directivity sending the power to somewhere is it not useful.? When you think about shortened antennas, consider that the field generated by a short wire is going to be considerably smaller than a full size wire.? In the case of the described antenna above, I have no doubt that the antenna will present a matched load at the transmitter and it likely radiates some signal.? However, look at the wire in the cylinder and realize that the resistance of the wire in the cylinder is not radiating but it is dissipating power just like any other resistance.? I suggest that that the cylinder radiates very little as the radiation of the wires folded end to end likely cancel each other out. That does not make it a bad antenna!
There are several antenna design in the Antenna handbook that play with black magic to get the antenna to radiate on the low bands, 160 and 80.? Some actually will use large diameter coax for the radiator or will use pipe to play with the L/D ratio or one really unique design uses a combination of lengths of coax to resonate the antenna in two closely spaced frequencies to broaden the antenna bandwidth.
I would like to point out that the handbook also has some great drawings on the current distribution in antennas.? Take note of the vertical that has a large inductor at the base or center and see the disturbance in the antenna current.? Visualize the current generating a field and you can see that these antennas may still deliver full power at the input of the transmission line, but all of that does not translate into current in the radiator.
As to the use of baluns and their mention in the handbook, of course baluns are mentioned for use with dipoles.? The dipole fed at the center or even off center are balanced loads.? If the antenna is fed with coax, then an imbalance is produced.? That translates to feed line radiation which may (most often does) affect the radiation of the antenna due to fields cancellation.? If one uses a balun to couple the balanced load with the unbalanced transmission line, balance is restored and radiation of the feed line is minimized.
As to comparing with antenna performance with dipoles or an isotropic radiator, that method is valid.? We know what an isotropic radiator field will look like and what load it presents.? To compare the antenna above with a full size half wave dipole at the same location and height would be useful for someone considering the design to match criteria at their QTH.? All of us have used various antennas for years.? We all have had contacts confirmed from DX stations, many with QRP, but that does not mean the antenna is better than others.? It means you can use that antenna to transmit to someone in that location sometimes.? Remember the old adage, "you can get a wet noodle to radiate, it does not mean you should or would use that all the time".
--
Al Skierkiewicz
WB9UVJ

Comes in original box. Options TCXO-9 High-Stability Oscillator.W1GHZ Panadapter IF output. MH-31A8J Hand Mic, NC-72B Battery Charger. Antenna. Carry Strap.
Will Insure Package. Works great. Full Manual Set included.?

Thank you Ron N9EE/R, I'll keep your request?in mind.

On Mon, Feb 20, 2023 at 1:00 PM Ron Wright via <lt_wright_flg=[email protected]> wrote:

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.


?

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.


?