Extra Class Lesson 9.1, Basics of Antennas
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- เผยแพร่เมื่อ 6 ก.ค. 2024
- THIS VIDEO IS OBSOLETE. CLICK ON THE LINK BELOW TO GO TO THE VIDEO WHICH HAS BEEN UPDATED FOR VERSION 11 OF THE LICENSE MANUAL:
• Video
Here is your video introduction to section 9.1, Basics of Antennas, in the ARRL Extra Class License Manual for Ham Radio. Topics covered include antenna radiation patterns, gain, beamwidth, radiation resistance, feed point impedance, efficiency, polarization, and bandwidth. - วิทยาศาสตร์และเทคโนโลยี
Thank you so very much! You're that patient teacher I always wished I had when I was a kid with a hunger for learning such things. Now decades later I've finally found my teacher and I feel like I'm re-igniting some long forgotten fascination with this world of things---forgotten and left behind in frustration.
I have a bachelors degree in EE and this is incredibly helpful. This sort of teaching is absent in formal education these days. Thank you.
Thank you
I'm glad he is out here two. I have a general ticket and have played around with antenna since i was a kid. but i did not think that I could kill some one because of not thinking. and that I wanted my antenna to work from east to west. and dave used several big words that the meaning did not compute in my mind. Yes there is a lot that is not taught.
How do they teach this then? I didnt go to school so id have assumed this is how its taught
As always, Dave has a way of explaining the complex to a guy like me so that I can understand. Thanks, Dave! I'm taking on the Extra exam and using the ARRL study guide as my text. But, I always come running to this channel to get the classroom version which makes it all clearer.
Dave, you do an amazing job explaining all this stuff. Spent many hours listening to you. THANK YOU.
I sure do wish I had these videos when I studied for my licenses! What a great refresher!
I really appreciate the way the topic is presented and superbly explained.. Thanks a lot Mr. Casler.!
+SRINIVAS MALLAREDDYPETA You're welcome!
Thanks for having both thorough knowledge, and rock-solid presentation skills. You rock!
Thank you from the bottom of my heart for this video. You made the pages in my manual come to life!
Good afternoon Professor Casler! I am studying about antennas and radar by myself applied to remote sensing. Yours teaching and explations are so clear and high quality! Congratulatiobs!👏🏾👏🏾👏🏾👏🏾 "The man is eternal when your job is continuous! God bless you and have a Merry Christmans, for you and your Family! Jacareí- São Paulo-Brasil.
Thank you sir, I wish I had courses thought by people like you.
Thank you Dave, great explanation. So much beneficial for me to understand the topic.
Superb David, I taught the RAE here in the UK using many of the tips of explanation found in your video series. 73 de John Allsopp G4YDM Washington,(Ancestral Home George Washington) North East England. Stay safe and well in the U.S.A.
Thank you sir. This is the best explanation of antenna patterns I have ever watched. Very intuitive description , superb presentation and indeed accurate.
I would like to design my own antenna for a Radar receiver!. Outstanding Lecture!!! My first introduction to Antenna Design. I started reading a textbook on Antenna. This video is superb and really summarized with all details. Thank you, sir!
David - I have thoroughly enjoyed your instructional videos in preparation for my advancement to Extra Class license. 73's
I subscribed after watching one video. You're up there with w2aew when it comes to explaining this sort of stuff. It's also so much that I can't learn it all from watching a single video a single time.
OMG I love this guy!!! I wish I would have had him as a teacher when I was in school, I'd probably be an engineer rather than an electrician!!!!!! SUBSCRIBED
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Never to late.
Studying for my Extra, thank goodness for your channel! Thank You!
Great review, Dave, even after playing with wire in the air and antenna building for the past 5 years.
Very informative. And it is so rare to hear someone so articulate. Thanks! 73 from India. This is VU3BQY.
Brilliant! You're an excellent teacher, thanks!
You sir are one fine teacher. Thanks for the video.
If I put a vertical on top of a steel shop building, will it need radials?
Most useful and understandable Antenna explanation I have heard. Thank you sir, remain blessed.
Best ever explanation of antena. Thank yo, you are great, talented teacher.
My old TV's antenna is a piece of electric wire hanging from it... It may not be the best, but man this things are easy to make... Great video by the way! Very informative.
Great video, thanks for putting it together. I look forward to checking out more of your videos
David, U R STILL THE ONE !!!
Thank you so much for your lessons !
Alex
ki6eeo You're welcome!
Excellent presentation! Very very well done! Bravo to you!
Mr. David, thanks to you i know more about RF
Wow, this is a very good explanation. Thanks, Dave!
This is by far the best explanation of antennas I have ever come across. I've learned more from this video than in countless hours of browsing the web. Thank you!!
May I suggest adding the topics covered to the video description to help others find this amazing video?
Mark, thanks for the suggestion. I've updated the video description. 73, Dave
Sir you're good!! Thanks for your contributions, this is S21TB, 73
+Ahmad Sayem You're welcome!
Thank you very much for these videos. I know it took a LOT of time and energy to produce. This video helped me understand antenna gain better. 73 KK4VYS
Excellent instruction. Thanks.
GREAT Video ! Thank you! Better than a paid-for University Class...
fantastic video. Thank you for sharing a lot of beneficial information
Thank you Sir! You just made me a better engineer :)
You are an excellent teacher. Very clear explanations of hard to grasp concepts.
Tyler Snowden Thank you!
There are myriad ways to screw up the use of "myriad"....kudos to you, David, for knowing how to use the word correctly. Oh, and BTW, just an exceptional video on a very difficult (for me) topic. Thanks!
Great information. Getting close to my extra. Thank you
Great presentation. Thank you for your time.
Excellent contents and a gentleman as a presenter. There is many hours of preparation for such a video. The priority points are mentioned and his experience does admit that practical performances are not always as theory stated, His best statement concluded from his experience is ," Everything can affect the performance of the antenna." My congratulations on your presentation and experience.
Carmel Pule' Thank you
Thanks a lot for making and posting these lessons. I've just got my ham radio licence back and there's a lot I have to remember before I resume operations. I still have to decide which antenna suits me better. At first, I thought of an inverted v dipole, than I thought about a long wire. But since, I like dxing a lot, I may want to build a delta loop antenna. 73 from PY5WHO/PY5136SWL
Thank you, these are very helpful.
exactly the video i needed! thanks Sir!
Thanks for this amazing video.
Great, I found your amateur extra videos and your general videos.
Good luck with your studies!
You are a rock star teacher!
Thanks. Good post. I'm an antenna fanatic.
Well done Dave.
Wow Dave . Looking good!
Very informative, thank you. Now on to the not obsolete video, haha.
you're awesome i'll start watching your videos from the begining keep it on going plus i subscribed (;
thanks David very clear...
Deep. Well done. Better than 5 yr degree programme.
Thank you for the excellent video OM! 73 de AC6GM!
Extremely good!
Started a diy double cross antenna build for receiving satellite images and somehow ended up here in the weeds 😂
Sir , ve made it better to understand and develope
.thanks for the video
Thanks Dave & 73 - great lecture.. VA3PDG
Thank you for the video!
Very clear explanations.
cool stuff...really been helpful....thumbs up
Improve your antenna before investing in an amplifier = WRONG!!
The correct way is to invest in whichever one presents the sweet deal first. Get the other one later.
Great video btw!! I learned a lot from this one!
Better antenna is almost always a good upgrade.
thank you, very good video!
phenomenal lecture
Some people think that you should use a certain length of coax between your radio and swr meter when adjusting your antenna. What are your thoughts? Thank you. Larry
Thanks Dave!
Love your videos and how you present the material. I always learn something new. However, you've probably never been to Western Nebraska as it is NOT flat. Once you get past North Platte, you're rising in elevation and the hills become more apparent.
What is the best type of antenna to use if i want the main lobe to be a cone with maximum gain around the axis in the centre? I want a drone to to follow the maximum signal strength, in other words, the drone should always be going towards the central axis in the middle of the main lobe.
finished the whole vid mann nice
my god I almost understood I checked a few words and it's coming clearer thanks from don the welder
Great job !!!!!!
It's very helpful .thanks sir
Thanx !!! great great help
Might be "obsolete" as far as the current HAM radio exam. Certainly NOT obsolete in regards to real life learning. Outstanding presentation. Wish I knew which "book" he's refrencing.
He's referencing the ARRL Extra Class License book, this may be a little out of date but ~95% of the content hasn't changed much in the last 10 years.
Interesting.
Practical facts.
Dave thank you , I passed my Extra yesterday
de KJ6CQC /AE
Dean McCollom Congratulations on your upgrade!
Fantastic video thank you
Great David, thanks and good dx 'de IW2OBB
would you mind explaining the fundamentals of patch antennas
what should be the radiation pattern of multiband antenna
What is the relationship between receiving antenna configuration and transmitting antenna configuration for shortwave radio frequencies? My impression is that reception is less precise than transmission, and the most important characteristic is height. I want to try a weather ballon just under 500 ft with a 1/2 or 1/4 wave antenna out of a rigid material in a horizontal mode. Compass heading may have to be magnetic, ie, north- south. I’m a ME by education and practice. Be kind.
Do you have a video where you explain this in terms of Earth specifically?
Hey there Dave! Thanks for you & all the other You Tube University professors. My extra class status posted to the FCC data base, last week, or the week before. I managed to sail through the Technician & General, mainly from repairing AF & RF stuff for the past, uhhhhhhmm, erm, eh, carry the, and add the, uhm, wow. Let's just not go there. Anyway, thanks for explaining why a dipole does what it does & how the test got their figures. My QTH in between two AM stations, that tend to wreak havoc with everything. Antenna types I was never bothered by, were/are one of my weak areas. I am up in Colorado now, again and will be headed out your way soon. Who knows? Maybe? I generally drive & I don't even like even using a cell phone, while doing so. 73 KI7AQJ
+Seth B Congratulations on your upgrade!
Now I understand why there seems to be so much experimentation with antennas. I have LOS from my mailbox 600 yards to my workplace through a closed window. Being a run down rural road. I'm going to build a disk Yagi and mount it inside a newspaper tube aimed down the street. :)
complex topic but well explained, i feel video needs to be watched multiple times to get better understanding....
Thank you!
very clear ... thank
What do the new satellites looking at the edges of the universe use for a radiation pattern. It must be extremely focused because signal strengths are not in the megs watts.
Which is the best antenna to transmit and receive 915mhz frequency ?
you are awesome sir but i have a doubt that is why we are measure the bandwidth within the -3db line i am waiting for your answer
can you make a Yagi spinning antenna and get benefit of isometric antenna ??
I do have a question: what is the inportance of: R, R2, C, C2, Z, and Z2 in a broadcast fm antenna, most of the Engeeniring look for SWR, and dont care about the anterior measurements (R, R2, C, C2, Z, ad Z2)
Thank you.
Video link for updated version is "private" and thus not accessible. Thanks Walt KT0D
If the radiation pattern can be reduced, is it assumed that the antenna has more range? The power is concentrated over a smaller volume cross section therefore the pattern should be elongated?
This story might help some people understand radiation resistance: Back about the turn of the twentieth century a young patent clerk was trying to understand why antennas generated far fields. Applying Maxwell's Equations generated a near field, but no far field. After pondering the problem, he discarded everything everyone knew about physics and invented Special Relativity to solve the problem.
It turns out that accelerating charges changes their inertial reference frame and causes them to emit photons. One way of understanding antennas is to see them as guides to accelerating electrons so the photons they emit go in the directions you want.
But rather than teach every HAM radio guy Special Relativity, they started teaching "Radiation Resistance" instead. That worked for a long time, and Electrical Engineers forgot the physics behind their craft. But it's a nice tidbit to know, even if it's not that practical.
Thanks a lot :)
Why does the Signal Strenght indicator show the Signal is Stronger the futher away it is from the dipole antenna's element (radiator).
It's my understanding that an RF/Electromagnetic Wave falls in strenght based on the Inverse Square Law:
The Strength of the EM field is Inversely Proportional to the Distance Squared from the Radiating Antenna.