Re: results of new US antenna design - advice sought
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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.
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