#573c

[@rossbrawley]

I've been a antenna building enthusiast since I was 15. I'm 37 now so it's I've done my share of experiments and trial and error.... I have never in 20 min gotten so much understanding of why some antenna work and others don't.... WOW! You are my favorite elmer now! Great job.

[@IMSAIGuy]

Thank you

[@SpiralDogma1990]

Best video ever. Watched probably over 100 videos about antennas and this one clicked instantly. Just started with 11m CB radio a few weeks ago. Thank you very much

[@charlescartwright6367]

Aloha, the most entertaining explanation of transmission lines and antennas I have ever listened to. I am sure you have helped many of the younger generation of ham operators. Thanks for your time and efforts. Wouldn't it have been great to have the tiny-SA and the nano-VNA back in the 60's and 70's?

[@k19radio13]

Bless

[@clems6989]

love how excited you get over this subject. Lol good video !

[@Steelplayer59]

“Magic”. Yeah- you’re bringing the magic back to this hobby! Thanks for all the informative videos on the VNA and other test equipment we could only dream about years ago. I’m embarrassed to say I didn’t know that RF travels in the dielectric,despite being a ham for decades. Never too old to learn,I guess! I’ve built a few antennas,mainly by “recipes” and “seat of the pants”, so hoping that learning to use the NanoVNA will improve both my skills and antennas.

[@ThermalWorld_]

But what golden information for antenna technology. My Lora devices will now be more than happy with all this wonderful information for building antennas. Thank you man, you are gold for the knowledge of humanity. "If you can, maybe a few more episodes for the antennas would be nice. For many people, radio waves and antennas are still voodoo magic" 😅

[@tomkeady1750]

Thanks, this really pulled together some of the antenna information I've been trying to absorb (and retain) over the past few years. Finally able to begin to understand my NANOVNA as well. Really enjoy your enthusiasm. Nicely done.

[@arizona111]

Excellent vid! Pretty cool with your years of experience you are still so excited! Good stuff.

[@bitemykrank1970]

I like your enthusiam, when you were describing the similarity between LED's and Antenna's it was like listening to a kid in a candy store...and VERY a informative video from start to finish to boot...I learned a lot more about things that I don't fully understand.

[@davelapp4740]

I can honestly say I would never in a million years have expected to hear someone say solving Maxwell's equations was fun and sound like they actually mean it. I would have bet that they were being sarcastic. My hat's off to you!

[@IMSAIGuy]

well, matlab does the heavy lifting

[@davelapp4740]

@@IMSAIGuy I knew there had to be some secret :-)

[@DavidLopez-bz4rj]

I love modelling antennas, building, and now testing and adjusting with the NanoVna. And of course, using them.

[@sgifford1000]

Those EM waves are alive! Thanks, got my first VNA!

[@PapasDino]

I THINK the LPDA feed actually connects to all interconnected elements (usually at the smallest element) rather than the yagi feed point you showed for the log periodic. Nice to see your enthusiasm for the subject!

[@IMSAIGuy]

yes I think that is right with phase reversal on each element

[@98xjdriver]

Nice explanation of a discone. Appreciate the diagrams also.

[@IMSAIGuy]

I will be posting a video soon where I build a discone

[@MarcusPocus]

houww.. the electrons are happy now!! ..love the comic way you explain it!!!

[@LionRoars918]

I just bought a Nanovna for exactly this reason. I am looking forward to testing my homebrew ADS-B 1/4 wave antenna very soon.

[@tomstrum6259]

Thx for another informative demo..This explains why when building my CB ground plane antennas during my high school '60's,...the better looking & Intuitive "propper & correct" 90° angled ground plane radials produced discouraging High Vswr readings Despite length tuning attempts !!! ...Thx again for the cool video....?.tom

[@chriswalford4161]

Really interesting. Thank you. I’m not a radio guy, but about 30 years ago I discover the cat’s cradle of the curtain arrays at BBC Rampisham, and was just fascinated by these huge towers precariously (apparently) holding up a filigree of radiators and reflectors and shapes and layer to transmit HF to directed targets thousands of miles away. The sound of the wind whistling through them… Then I discovered that the radiating pattern from these fixed arrays could be slewed up to 15* in 2 dimensions by playing with phase shift and I realising I was trying to understand magic. Then they reduced the magic to dust. In phases from 2017, they dropped the arrays and pulled over the huge steel towers with their sinister hammerheads and the silhouettes on the down were gone, leaving tell-tale concrete anchor blocks and tower foundations buried.

[@needhelp2453]

Wow! Really interesting video. Thank you

[@johnwest7993]

The antenna array you mention may be the W5UN EME array in TX. It's not on tracks, but a computer-controlled vehicle chassis drives around in a circle to rotate it. Last I heard it had 64 long boom 2 meter horizontal and vertical Yagi beams.

[@IMSAIGuy]

I think it was this: K5GW, the owner of Texas Towers, has a full-sized 3-element 80-meter yagi that uses Rohn 45 as the boom. The elements have mechanisms which vary the length of the elements so that the antenna performs well over the entire 500 kHz of the band. Years ago, there was an amateur radio operator who had a rhombic mounted on floats on his farm pond ("tank" here in Texas) that he rotated with 2-electric powered tractors mounted on tracks around the pond. That antenna gave gain on 160-meters through 10-meters with the exception of 15-meters. This antenna was featured in QST one month. Glen, K9STH

[@combsrichard11]

Great explanations. I come from optics and love learning new insights for properties in the radio wave regime. Same effects but at a totally different scale. Lots to learn about these "big" radiators,😄👍

[@janina3473]

Wooow, you are amazing i wish i had teachers like you

[@rfmonkey4942]

nice , lots fun can be had with nano vna it really let people in the game who would not normally stand a chance i use them alot so compact !

[@technodruid]

You just gave me PTSD flashbacks to EM third year physics

[@judd_s5643]

I’ve tuned damaged (slight) wave guides using a ball peen hammer and a TDR!

[@TankmeUSA]

Big fan of yours and a beginner antenna builder myself!!! I would love some explanation of the way some vertical antennas are feed , example Excalibur.64 or a maco v 5000 , that is what gets me a little confused

[@IMSAIGuy]

I'll add it to the list

[@TankmeUSA]

@@IMSAIGuy thanks!!! here is a link to one of my first attempts without understanding the concept entirely. I would like to hear your critical opinion . kzbin.info/www/bejne/i3unaYtqZbl-q7M

[@IMSAIGuy]

@@TankmeUSA looks like fun. I probably would have just put in four radials to the corners, but I'm lazy.

[@MrBanzoid]

Thanks for your informative and enthusiastic video. You really know your stuff! Cheers Malc M0IYI

[@IMSAIGuy]

Thanks

[@ThinklikeTesla]

IMSAI Guy, what references do you recommend for learning antenna physics, 3D Maxwell's equations, and so on? Currently making my way through Div, Grad, Curl, and All That: An Informal Text on Vector Calculus. (with the ARRL Antenna book waiting in the wings)

[@IMSAIGuy]

Well I'm pretty old to be giving that advice. Got my degree in 1979. My textbook was: Electromagnetic fields and waves by Paul Lorrain and Dale Corson. It was the basics of E&M but did not touch on antennas much.

[@IMSAIGuy]

eduguidehome.files.wordpress.com/2019/03/electromagnetic-fields-and-waves-by-paul-lorrain.pdf

[@ahmedgaafar5369]

I really wish you were my professor during University.

[@Bruce-f2r]

Could you do a Video on a OP-Amp Log Amp with a feed back Diode and how to Caill uate the Output Voltage Thanks.

[@orhanboyac3693]

thankyou

[@vidasvv]

What a great explanation ! 73 N8AUM

[@egbertgroot2737]

That was an easy impedance match! ;-)

[@seanmangan2769]

What is an E and M wave?!? I know what an EM wave is...

[@warplanner8852]

"..don't ask me why.." Because you said a 1/2 wave dipole antenna's impedance is 73 ohms and your 1/4 vertical impedance was 23 ohms. If you had bent the radials down all the way, the antenna would resemble a half wave dipole and probably have an impedance close to the 73 ohms. I am sure the impedance is not linear from the 90 degree point to the "180 degree" point, but proportional. Try it. I did.

[@tahirsongelen7781]

ALL YR TOPICS ARE EXCELENT I AM FOLLOWER 73 TA1BJ

[@IMSAIGuy]

Thanks and welcome

[@k19radio13]