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Mike, My point was not who likes or dislikes small loop antennas but for any antenna can be calculated or estimated the gain figure or its antenna factor. During my dialog with well respected Martin

Rafael, The article is about a shielded tuned loop with a split capacitor matching to 50 Ohm. 30dB loss on 7MHz compared to a full size dipole is not bad at all for a receive only antenna. Maybe a

Good evening Martin, I found for you a paper published by Duffy at his blog https://owenduffy.net/antenna/shieldedloop/index.htm Please read this article especially at its end where he points out

The attachments on my earlier posts regarding Linux updates were stripped somewhere along the way. So I have placed the attachments for both Linux Mint and Raspberry Pi OS in the following Dropbox

The mentioned article/file is uploaded as “Antenna_Paper_Part3.pdf” Sent: Sunday, October 30, 2022 3:37 PM To: [email protected] Subject: Re: [loopantennas] Optimizing Small Untuned Loop

Raphael Wasserman <wassermanr46@...> added folder */Antenna Mismatch and Effiiciency Factors* --- The following files and folders have been uploaded to the Files area of the

All, I am attaching an interesting article where are described factors such as antenna efficiency and antenna mismatch that will effect AF value. This will let you re-think I have not yet introduced

The STLcalc program file needs to have permissions set to executable mode, a fact which I failed to note in the README file. I have edited the README file (attached) to add a step that describes this

The STLcalc program file needs to have permissions set to executable mode, a fact which I failed to note in the README file. I have edited the README file (attached) to add a step that describes this

Hi Martin, 1. I was interested to know how works Duffy's published calculator for small loops. Of course, all intermediate steps of calculations with this device were unknown for me but Duffy did

But in a later post you say:- The efficiency will be the same for tuned or untuned small loop antennas because neither radiation resistance nor loops ohmic loss can be changed These seem to be

Rick, 1. The efficiency of antenna K is defined as a ratio of (R radiation/ R radiation + R antenna loss), where R radiation value is significantly less than R antenna loss regardless tuned or untuned

What can be proven is that the inductive reactance is cancelled out in the case of the tuned loop, but not the untuned loop. I'm not sure what definition of "efficiency" you are using, but a tuned

Rick, The efficiency will be the same for tuned or untuned small loop antennas because neither radiation resistance nor loops ohmic loss can be changed...unless you can prove otherwise.

You would be doing well to get 1% efficiency with a TUNED loop. For a small UNtuned loop it would be more like 0.1% efficiency or less. Rick N6RK

All, Since I have Kraus's book "Antennas for all applications" as my technical bible, I re-read the chapter 6 about loop antennas. He does not use at all in the terminology AF but *effective antenna

Hi Martin, I reviewed recent Duffy's comments in the mentioned blog. Duffy states: *AF db/m= E dBV/m - V dBv,* defining the antenna factor. It is taking without any argument regarding it. For some

A recent comment on Owen Duffy's blog regarding AF. https://owenduffy.net/blog/?p=27134 Regards, Martin

Hi Jeff For 160m? I suggest you think about the antenna described here ( https://topbandhams.com/tech-page/76-wb5wpa-1-4-wave-tuned-vertical-loop ) on the top band hams reflector.? The way WB5WPA

Hello Jeff. A small transmitting loop (STL), or mag loop for 160m is possible, but some compromises must be accepted. I built a three-turn STL for 80-160m use about 12 years ago and have had good