The Yagi-Uda Antenna - Lesson 3

[@lerneninverschiedenenforme7513]

Highly underrated material! Thank you very much for the work!

[@emviso]

Thank you!

[@waylonk2453]

Thanks for posting this on KZbin. The visuals are the best I've seen so far when learning about this antenna design.

[@Earth-Worm-Tim]

I would move to the awful state of NC to continue with my Ph.D. if I could learn from her! Throughout my entire BSEE and MSEE curriculums and 6 years in the RF Engineering industry, never have I ever met anyone who could explain these topics as clearly as she does. If these playlists existed back when I first began my graduate coursework with an emphasis in applied EM and antenna theory and design, I’d of progressed significantly faster. If you’re studying RF/Microwave Engineering and you’re NOT watching her videos, you’re either unaware they exist, or a glutton for punishment doomed to exist in complex exponential HELL as a means to make sense of antenna design through abstract mathematics (as is the conventional method) given what I believe to be a lack of professors with her level of comprehension in academia.

[@racebike6160]

Speaking as a retired RF Systems engineer, I agree 100 % with your assessment of her teaching abilities

[@TheMuffinMan-m8]

Thank you for visualizing it like that. Very helpful.

[@glenmartin2437]

Thanks. That was a pithy, concise review. Keep the videos coming.

[@johngranato2673]

Great explanation, young lady. Thanks a Million!

[@JulietNovember9]

Great explanation. It was voodoo to me before!

[@stevenjenks9789]

Very good presentation 😊

[@CaseyStanton]

This is so easy to understand. Great job!

[@emviso]

Thank you!

[@nwadeswim]

Thanks so much! This material is fantastic!

[@Javierriveraab]

Thank you very much for the explanation , professor!!

[@kcoRwobniaR]

Thanks ! Great material to begin with.

[@emviso]

Thank you for the feedback!

[@tomstrum6259]

Thx for the video...What Causes the Inductive Reactive element (the Longest element) to Reflect rf energy back towards the Driven Dipole element ? Also, what causes the Capacitive Reactive (cascading Shortest) elements to steer rf energy Foward away From the Driven Dipole element ?? Why are Parasitic Elements specifically 5% Different in Length and Why are Parasitic element Spacings usually Near a 1/4 wavelength Boom Spacing ? How were long multi element Yagis designed Before computer models ? Thx.....

[@Kope-p5f]

Great video, much appreciated.

[@jluke6861]

Thank you for the Great Video.

[@georgebreckenridge3351]

Great job! Thanks

[@wesKEVQJ]

Thank you for the very informative video.

[@garylanders1470]

Hello Kathryn I would like to ask if it would be feasible and at all beneficial to have multiple Yagi antennas all equally tuned and at the same hight but in a circular array. For example having six Yagi antennas forming a star pattern so as to push the +dB signal out in more of a wabbley circular pattern (Non collinear). Thank you kindly for sharing your knowledge

[@RP4886]

Great video. Thank you

[@danda.117]

日本にはもっと素晴らしい発明がたくさん有る🇯🇵万歳

[@jayjay-gl4fj]

Good video!!

[@lawrencecohen1619]

Excellent description and visuals of the Yagi antenna.

[@emviso]

Thank you!

[@surendrakverma555]

Good 👍

[@compuguy123]

What if you have a vertical and horizontal element 90 degrees from each other?

[@azizulhakimbappy3253]

Thank you

[@jeffreycanipe1936]

I just found this author and i really enjoy the lessons. Being a ham radio operator, i am very interested in building a 70 cm (approx: 443 MHz) yagi. Thank you.

[@timetraveler7]

What should the length of the antenna be? Does it need to be half wave dipole or can it be short dipole?

[@emviso]

The driven antenna is typically a half-wave dipole.

[@timetraveler7]

@@emviso would having a yagi antenna with a short dipole increase gain?

[@Doonit_hard_way_since_65]

@@emviso a 1/2 wave dipole will drop to around 20-ish ohms as a result of the proximity of the parasitic elements. You are going to need some form of matching, or you are going to see inefficiency, and in the case of a typical transmitting antenna... magic smoke getting out of the finals.

[@FFdo.]

depends on what are your needs you can try with a 1/4 wave length as well if you are working lower bands like 1.6, 3.5 or 7Mhz. for 7M/40m a 10m driven element will work fine with one reflector and one director.

[@keithmarkcam6216]

Thanks for the information

[@emviso]

Thank you for the comment!

[@jhonphil1237]

best explanation

[@emviso]

Thank you!

[@trainmaster0217]

I never can get a reflector to work with the antenna I have built....no matter the spacing. The signal level always drops with a reflector.

[@erkintek]

Directors should connected with each other?

[@macadameane]

no, directors and the reflector are straight conductive elements that aren't connected electrically to anything. the dipole should be split down the center, but not the others.

[@anupammathur17]

Shouldn't a yagi have a folded dipole as driven antenna for the purpose of higher directivity and gain?

[@Doonit_hard_way_since_65]

Folded dipole is used because of it's higher characteristic impedance (2-300ohm). The parasitic elements have an effect of dropping the driven element feed impedance. a straight dipole's characteristic 75 ohm impedance would fall into the single digits without some form of matching. We can get around 50 ohms with a folded dipole without needing a gama match, or some other form of matched feed point alteration.

[@anupammathur17]

@@Doonit_hard_way_since_65 Thanks👍

[@ireadursoul]

what happen when yagi has a reflector - driven and no director?

[@sidb6471]

thank you so much

[@emviso]

You're very welcome! =)

[@soaperino]

@@emviso thank you!

[@emviso]

@@soaperino Thank you!

[@idonthaveaname42]

really cool

[@ahmedmoustafa6829]

Thx

[@JaraFPV]

What will happen if the reflector and directors are not aligned in the center? Say the directors are all aligned at the bottom instead of them having on the center of the reflector?

[@emviso]

Simulate it and find out! www.ansys.com/academic/students

[@TyWooly42]

Great information. Too bad you don't have a better microphone.

[@itrstt66]

it seems liek the director has a parasitic refletcion effect, is it right?

[@examplerkey]

Best!

[@usamamumtaz1378]

Good

[@soaperino]

yes