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Justin! Nice to see you dropping videos! Woo-Hoo!

G'day Justin, great video, thank you for the detailed description. A question about mounting the 1/4 stub balun - once the stub balun is heat shrunk to the feed coax, can they both be then zip tied to the boom, or should they be kept away from the boom for at least the length of the stub (like what you recommend when using the ferrite chokes)?

Great video - thanks. But your web page server has some troubles with redirections. Next I would like to see 144MHz beam modeled in NEC-5

Hi Justin I tried to go to your G0KSC web page with the link you put in the info it just not working many thanks 73

Thanks for excellent video, I would like further explanation on baluns. It was clear how to determine the 1/4w stub length but what is it actually doing? 70cms next please

Hello Justin, please. do you have a schematic for 15 meters LFA!?

Thank you for the video. I did a bit of dabbling on 6 meters in 2024. Using an oblong loop and a hf loop. The makeshift antennas were just good enough to pique my interest, So I am ready to improve on it. You can tell when other local stations are running the LFA Yagi because they always do well. This is great timing, because I would like to learn how to build one for 6 meters. Please keep the RUclips videos coming. 73, K1QS. P.S. I really am interested in that Balun. Can that be used for other types of antennas?

Would it be possible to model antenna with boom and through hole mounts with NEC-5 ?

These highlighted subtitles do my nut in!

I have come to the conclusion that for well behaved Yagi models, NEC 4 may be more accurate than NEC 5. L.B. Cebik carefully developed some Yagi models to reduce the NEC 4 and NEC 2 errors to a minimum. The article can be found by searching for "Modeling Six Long-Boom Yagis by L. B. Cebik". I modeled several of these Yagis with NEC 5 and the more segments I added the closer the NEC 5 results came to NEC 4, but they never converged. I stopped when the segments reached 100x the count in the original Cebik model. The documentation for NEC 5 also cautions against using NEC 5 for Yagi modeling due to the convergence issues. From your video, I have to conclude that NEC 5 would be superior when the model is not well suited for NEC2/4, i.e. stepped diameter issues, loop fed, close space wires. But for well behaved models NEC 4 may be more accurate. Regarding close spaced wires, I have found that NEC 5 appears to resolve the close space wired problems in NEC2/4 as I am getting accurate results for a Fan Dipole with the 40m and 20m wires spaced 4" appart and not needing to match the segment lengths. NEC 5 does not seem sensitive at all to matching the segment junctions across the wires.

I've just been getting started with designing and building antennas, and your videos old and new have been extremely useful! I wish I had watched this one a week ago, before I tried to build my first (2m) antenna with several inches of unmodeled feed point tails!

Same vid from the 23 Oct.

Where i can get model files, for trying by myself?

Hello Justin Justin here .. we love the LFAQ rigid

I still use your lfa design

I am a big fan of MFJ equipment and I am sad that it is shutting down.

Could you do a retirement interview with Martin Jue? I want to know how he feels about his legacy.

Original Sigma 4! I read a forums contributions on this that went on for years. Prob still out there on tinternet. Some great work done & commentary from very knowledgable people. It’d been modelled in some fashion. Maybe today’s software can get closer to what’s occurring. Assume the vectra copy’s had some upto date modelling/experimentation done. But for the above task - I mention it just for fun - if fun could be had?! A chap used the design for vhf/uhf & sold many antennas based on it. Clever chap. The only other antenna that springs to mind for me was Cushcraft X7. A beast of an antenna. My interest would be re-use of the antenna if broken down into parts. Could prob build numerous antennas with the components. I have one - given to friend to store - but I’ll doubt I’ll ever be able to use - but may well be able to use parts in the future.

Why cant we just have a program that is easy. EG I want a 2 element Delta loop for 10m press a button and you get the parts needed list, plan and instructions. Is there software available to do this

AMARAL PESCADOR PW8BR/ RONDÔNIA GOKSC 73

Nice, good to see you back doing videos Justin, thank you and look forward to the next one.

Nice to see that you are back Justin. Maybe a video explaining some of the different designs that are now available. LFA, OWL, OWA, bended dipole designs. There are a lot of choices out there. best 73 Jan ON6ZG/DL6ZG.

Looking forward to the next video

Great video ! thank you Martin. Testing now and it is not so easy and fast with long yagi, 73 SO3Z

Thanks Justin. Could you zoom into the text as very difficult to read. How would EZNEC NEC4 / 5 compare when using Ansys HFSS? In time will you be discussing this?

Thank you for the excellent video.

More great stuff, Justin; thanks! 🙂

well come back, Justin. Can’t wait for seeing your new work. 73, Max

As curved elements can now be accurately modelled, I would love to see a comparison between a 3 or 4 element quad with circular elements versus the usual square/diamond/rectangle. We know the circle provides more area, and thus better performance, but it would be interesting to see whether there's much extra gain to be had, or any other properties that emerge.

GREAT TO HAVE YOU BACK JUSTIN!!!! My wish list would be to see: 1: J-Pole antenna with better gain. 2. Modeling a Ham Stick antenna but finding the optimal loading coil position and antenna length. -80m I have a number of Han Stick Antennas from Moonraker that work well, but the 80m does not perform well. Have you looked at SimNEC written by Ward Harriman AE6TY? Stan M0HYY

Multi band antennas are very interesting. Your video of issues with 2m+70cm also was very enlightening.

I purchased a MFJ 834H from Moonraker a couple of week ago to test a new vertical 80m array. Service from Moonraker was awesome. They shipped to Australia in 10 days. Great to see you back Justin. VK4UC.

Sorry mate, unsubscribt. What a bulsh*t add..

Is the optimzer smart enough to stop at some point? I don't see where you enter target values to achieve, eg. SWR < 1.1:1 or F/R > 25.

where can i view how to do the improvement video?

Where is your fitness channel?

My observation is that 4NEC2 doesn’t seem to like *END FED* wire antennas (or maybe I’m doing something wrong). I entered a couple of designs that *WORK* for other hams, but when I analyze them, I get wildly high SWR figures. Yes, I have set the characteristic impedance to 450Ω or 2450Ω to account for the UNUN ratio, but it’s hard to see how they’d work. Ive added a counterpoise and allowed 4NEC2 to optimize the radiator and counterpoise lengths, but if/when they produce a _”reasonable”_ SWR, the resultant values are wildly impractical. Also (this may be covered in a subsequent video), is there a way to get 4NEC2 to optimize for multiple bands, in the case of a multi-band antenna? *73 de AF6AS in **_“DM13”_** land*

What happened to the video on the j-pole? You rushed through the explanation at the end. Please give us the details.

You lost me at "there is no need to have any matching" and "there is going to be loss". Sorry, but basic, 3rd year Analog Electronics theory is completely against your stance. Good luck making a 160m transmitting line-antenna system. Even transmission line lenght affects a system's impedance.

hi.. im having trouble with your web site im unable to scroll to the bottom of the antennas section.. i cant see all the options from 432mhz yagis and below.. the old website had no problem,, im on a laptop

Let's see it. Well I guess it's not gonna happen

CU2IJ. Nice channel and very usefull the series about 4nec2 since it seams to be the only decent antenna software running without problems in linux/Wine

To bad they closing down 😢 may 17th

Hi Guy! With which software can I simulate the effects of my (grounded) balcony rails on my delta loop antenna? I mean construct a complex ground structure(the rails). My bottom, horizomtal side of the delta is behind the rails, metal 1m spacing, lamda is 10m. Thank you! 73

Great stuff 👏🏽nice 👍🏽

Let's see your improvement! Thanks

I would like to see how to get more gain out of j-pole.

Yes, yesterday, as I’m right in the midst of creating my jPole

Great explanation of how to use symbols to speed up entering and allow you to use the optimiser.

interested