First resonate a short antenna, then impedance match it ?

[kellogs]

Or incorporate the reactive resonator component (one capacitor or one inductor) into the impedance matching network, any difference besides lower component count ?

 

[Delta Prime]

any difference besides lower component count ?

Your question makes no sense.
You must possess a firm foundation based on theory before you start designing anything.Please elaborate.
Is this a 50 ohm transmission line?
What frequency?
Physical length of an antenna can be designed to achieve resonance at a particular frequency wavelength
What are your size constraints for your antenna? Reactive, components, inductors, capacitors series, and or parallel networks are designed to match, not only transmission line but adjusting the input antennas impedance to minimize signal reflections & maximizing power transfer.

 

[kellogs]

Not sure why it makes no sense. Let me give my simple reasoning:

small antenna are not resonant on the intended frequency, otherwise they would not be small.

Their reactance can be cancelled by means of one series element - eg. an inductor for the short monopole antenna, or a capacitor for the small loop antenna.

The remaining resistance will be (almost?) always smaller than the expected 50 ohm, so an impedance matching network must be used.

Makes sense ? My question is whether there is anything to gain by first resonating the reactance away with one series such component before the impedance matching network, as we look from the antenna towards the receiver IC.

 

[Delta Prime]

small antenna are not resonant on the intended frequency, otherwise they would not be small

This is exercise and futility show me the math I need numbers. I need values component values frequencies you’re talking out of your azz.

 

[poormystic]

Yes, "small" antennas can be very useful at lots of interesting tasks - like "short" bits of string. The thing is: how short? Different kinds of signals require different antennas.
And most importantly - what would you like to achieve?


Edit...
My guess is that Kellogs needs a painless way to match an indifferent aerial to the input of a decent receiver. He wants to pull in more radio stations, in other words.
Is that about right, Kellogs?

 

[bertus]

Hello,

If you want to know more about antennas, have a look at these 3 arrl books:

The ARRL Antenna Compendium, volumes 1-3 : ARRL : Free Download, Borrow, and Streaming : Internet Archive

Date of publication:vol 1 - 1985vol 2 - 1989vol 3 - 1992Created from available scans.Good quality, small PDFs with OCR.

archive.org

Bertus

 

[kellogs]

Yes, "small" antennas can be very useful at lots of interesting tasks - like "short" bits of string. The thing is: how short? Different kinds of signals require different antennas.
And most importantly - what would you like to achieve?


Edit...
My guess is that Kellogs needs a painless way to match an indifferent aerial to the input of a decent receiver. He wants to pull in more radio stations, in other words.
Is that about right, Kellogs?

I m afraid not...

Anyway, the clear answer to my clear question is: no, it makes no sense to first resonate an antenna by means of adding a lumped element in series (capacitor or inductor); just match it as it is. It would have made sense to first resonate it by operating on the antenna itself, i.e. shorten / lengthen, load, fold, etc.

 

[Delta Prime]

It would have made sense to first resonate it by operating on the antenna itself, i.e. shorten / lengthen, load, fold, etc

Physical length of an antenna can be designed to achieve resonance at a particular frequency wavelength
What are your size constraints for your antenna?

What we have here is a failure to communicate. Some people you just cannot reach!
A quote,from the movie:Cool Hand Luke.
And coined in the lyrics from the song “nothing else matters” by Metallica!
“Booyah” you have just been DP’ed.
-Delta Prime

 

[hevans1944]

Aw, come on guys... simple answer is to add an impedance in series with the feedline that will cause the "antenna" to resonate. Then insert an antenna tuner between this kluge and your rig. Depending on the impedance you get after resonating the antenna, you may have to build or buy the antenna tuner. My KX3 can tune up and load into a set of bed springs, but that doesn't mean that's an ideal antenna. But that's running barefoot. Add the 200 watt linear amplifier only if you have a real antenna.

If you just take a random length of wire and end-feed it, you are looking at some very high impedance to match, resonating or not. A unun (unbalanced coax feed to unbalanced end-fed) helps you get there, but I would suggest you follow the advice that @bertus posted. And get a ham license, if you don't already have one, then find an Elmer to help you. Maybe join a local amateur radio club.

 

[Delta Prime]

Aw, come on guys... simple answer is to add an impedance in series with the feedline that will cause the "antenna" to resonate

Reactive, components, inductors, capacitors series, and or parallel networks are designed to match, not only transmission line but adjusting the input antennas impedance to minimize signal reflections & maximizing power transfer.

I enjoy reading your post; It pleases me that you have responded

 

[hevans1944]

Thank you @Delta Prime I have been busy elsewhere, mainly on X (formerly Twitter) conversing with Grok 3 [beta] on my optical-EME proof-of-concept demonstration. Starting to get a little traction on this, but if you want to see what I've been up to please visit (and ask to join: I will approve you even if you don't have a ham license) https://optical-eme.groups.io

I don't visit MakerPro very much anymore. With the exception of you, the quality of responses as well as the intelligence (if any) behind the questions posed here have declined significantly since it was Electronics Point. Oh, well, trolls to the left of me, trolls to the right, and here I am stuck in middle with you. Thanks for responding. Is it possible to shoot back at drive by posters? Everyone is too busy for a dialog anymore.

 

[Delta Prime]

Starting to get a little traction on this, but if you want to see what I've been up to please visit (and ask to join: I will approve you even if you don't have a ham license) https://optical-eme.groups.io

My gratitude for the invitation it’s always good to know someone on the inside I highly recommend!
You’ll find me there…

Physics Forums

Join Physics Forums, where students, scientists, and enthusiasts come together to explore and discuss the current understanding and practice of various scientific fields.

www.physicsforums.com

 

[bertus]

Hello,

Even the older ARRL books will have a lot of information.
This page has a couple for you:

BOOKSHELF ARRL HANDBOOKS: Ham Radio technical reference books

ARRL Handbooks: Ham Radio technical reference books

www.worldradiohistory.com

Bertus

 

[hevans1944]

Thanks for the invite to the Physics Forum. I joined, but immediately realized I had stepped into something waaay above my level of incompetence. Thanks anyway.

 

[Delta Prime]

immediately realized I had stepped into something waaay above my level of incompetence. Thanks anyway.

As an undergraduate student, I beg to differ… Your posts here on Maker Pro. Your style of conveying information offers a different approach to attack a complex circuit, that I have never considered before. Thank you for that!

 

[hevans1944]

I joined Physics Forum (at your suggestion) because I need some "fact checking" on my optical designs for the transmitter and the receiver that I will use to demonstrate a "proof of concept" for amateur radio optical EME communications. So far, all I have received is "can't be done" responses from first responders who haven't bothered to visit and read what I am proposing. If you would like to participate in this quest, I would appreciate it. If not, please visit https://optical-eme.groups.io anyway and tell what you think.

It is very old technology, or at least the theory is. Claude Shannon, working for AT&T IIRC, developed information theory and the relationship between data rate, bandwidth, signal-to-noise ratio, and error-free communications. After the first trans-Atlantic telephone cable was laid, they found out that distributed inductance and distributed capacitance determined the effective bandwidth of signals propagating on the cable. Shannon provided the theory, but it wasn't until this century that it became affordable for amateur radio communications.

Here it is in a nutshell: if you add a priori known information to a signal, that signal can be recovered without error. It doesn't matter what the signal-to-noise ratio of the comm channel is because that just affects how long it takes the recover the "message" which is repeated as often as necessary until the noise integrates to zero and the message rises above the noise.

Unfortunately, the signal loss for EME comms is huge. That didn't stop wealthy hams with deep pockets from building Yagi-Uda directional arrays, or microwave dish antennas, on alt-az mounts and "shooting the Moon" with kilowatt transmitters and Collins rigs in the 1950s. Fast forward a few years and another ham used Shannon's theories to invent Weak Signal digital communication techniques. That is now used by hams worldwide for VHF, UHF, and microwave EME communications. A forum is available: https://wsjtgroup.groups.io.

 

[bertus]

Hello,

@hevans1944 , Do you know project ronja?
It is about an optical kind of data link:

Home

This is advanced menu for Twibright Ronja Optical Datalink Project, a FSO device realized as free technology.

ronja.twibright.com

Bertus

 

[hevans1944]

Hello,

@hevans1944 , Do you know project ronja?
It is about an optical kind of data link:

Home

This is advanced menu for Twibright Ronja Optical Datalink Project, a FSO device realized as free technology.

ronja.twibright.com

Bertus

Wasn't aware of this, but I did help a friend install unlicensed, low-power, wireless data links in office towers in downtown Dayton OH USA. The optical approach has the advantage of also not requiring a license. I also know a ham, Rex VK7MO, in Australia who is doing optical line-of-sight and "cloud bounce" comms with largish arrays of visible red and near-infrared LEDs. He uses Fresnel lens, one for each high-powered LED, and a single lens focused on an APD for the receiver. He quit using visible red LEDs because people would see the glow on their horizon and call authorities to warn of the "forest fire"!

Hop - AC8NS