How AM and FM Works
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- Опубликовано: 27 июн 2012
- Highly edited version of US Army training video (TF11-3482 - Frequency Modulation Part I: Basic Principles, 1964) on the basics of FM transmission. This also shows how AM works. For educational purposes for my students.
I was expecting a video by prominent modern educators on RUclips like Veritasium, Smarter Every Day or Khan Academy but it turns out that the best explanation I've ever seen on the topic is by a video made decades before I was even born
Lol it's ok, I guess the the past is better. Also I was expecting a nice video from them too lol
*****
Making videos with great analogy and animation was pretty hard back then and still is now, but it's relatively easier to make.
Notice that this video was made by the US military. I'm guessing only they could convince animators back then to make such videos. =P
It's in the military's interest to explain everything clearly so that everyone will understand.
This goes for most things. The old sayings usually still ring true as well. They just don't make em like they used to.
@@Tuppoo94
It's also in every educators "best interest" to make sure people understand what they're saying lol
These old training videos often surpass our modern multimedia productions. This is an example of the high quality instruction products of the past. Easy to follow, clear and well illustrated. Good stuff!
Modern audience would have a really hard time sitting through this because it is too long and explains EVERY little thing.
It is good and bad at the same time.
A modern multimedia educational content would have summed it up in less than 5 minutes, however it wouldn't be as magical.
@@HAWXLEADER are u saying the newer generation is less intelligent?
@@GamePois0n Not less intelligent but less patient, we want everything to be fast and easy to digest. That's why we have TikTok-like video feeds being so popular.
This is the best explanation of AM and FM that I've yet seen.
I didnt even know about AM before, we dont have any AM radio stations in Finland and its not used for anything. All radio is FM.
Suomi mainittu, torilla tavataan!
we have still many working AM radio station in India !
Tuppoo94 exactly!!!! Never seen a video with crystal clear explanation like this one. Other videos just explain conventionally like u know withe mathematical terms and stuff. But this is next level explanation. ...
100% agree
I am an instructor at a US Army school and we love using this video. It still works for the basic understanding level and the students get a kick out of a space race age video.
Joshua Rambo What is kinda cool too is that without intending to do so, it explains single side band.
Nostalgia and education rolled into one. Loved it! Currently studying for my Ham Radio exams so this is a gem. Thank you.
This is the way of teaching that we expect in college but unfortunately we don't have it in college.
Love the old explanations. They explain it in a way I can understand.
Same here.
I am compelled to say how wonderfully clear this video is on AM and FM modulation. I saw a few modern explanation videos before watching this. Those other ones were impossibly wordy and lacked in clarity. Thank you !
The old black and white tapes amazingly describe it all.
these old videos are awesome. such amazing and simple explanations in both the visual and audio. great stuff.
This is a very good (and still relevant) film! I "always" knew how AM worked, And had an idea about how FM worker, But this EXPLAINS it. Decades later, FM is still ingenious! Armstrong was a genius! First, he gave us Superheterodyne, and later FM.
Old videos like these always explain so much better visually.
Thank you so much!! Now I finally understand what my teacher is talking about....
Wow, what an excellent and thorough explanation! One can visualize the concepts so clearly! Thank you very much for sharing!
I’m currently in Air Force tech school learning how to repair radios and radars like these. This video made everything I was leaning in class click
This video was probably shown at your tech school during Vietnam.
These old videos are the best!
They made hard things understandable back then and called it teaching. They knew that entertainment doesn't instruct. Good instruction entertains.
Jeez, this is the best explanation I've ever heard!
Thank you! This is the best explanation of AM and FM that I've ever seen!
Best explanation ever... I hope part 2 and other videos are available which discusses about FM circuits.
Incredibly good explanations! Still as valid, today, as the day the video was made.
Great respect for this video teaching quality and the animation with the means of that time!! Feeling grateful!
IN THE PAST PEOPLE WERE SMARTER, WEREN´T THEY? no tik-tok explanation... this is an almost astronaut´s explanation. The best I´ve seen!
Really excellent explanation...which I really need right now. Thanks for the posting. I'll hit it a few more times over the next few days until its all sunk in.
Thank you for sharing this. The visitors to my forums will find this quite helpful.
A very very useful basic lesson. Thanks for making it available.
Thank you so much for sharing the very comprehensive video.
This is one of the best explanation ever.
This is the best video about AM and FM yet. (Even though it's age is over 50 years)
Amazing I saw this at south eastern signal school 1971 .
now that's what it is call a well done job.... putting a video together!!!!! ;-)
Cheers to US Army and the Uploader!
just PERFECT ! many thanks for sharing !
Thank You! This is a very good explanation I sent along to my buddy!
If you know FL Studio, you can recreate the same thing in Sytrus, it is pretty interesting to hear! You can individually listen to the "coded" (modulated) and the original signal. Use a Wave Candy to visualize the whole thing.
I want this guy to teach me everything about every machine. Today people are too worried about their personalities and asking you to subscribe in between
Most informative video on the subject by far
thank you for this amazing video
I agree with all of the previous positive comments. I always view these "antique" videos first when I want a clear explanation. Thank you U.S. Army.
Reminds me of that “If woody would have went straight to the police, this would never have happened” guy.
Explained well in simplest way ever
Wow! Very interesting video. Well done and thanks for sharing.
Awesome! Very informative!
Wow great video. The others baffled me with maths but this one i get. It took the United States Army to make me understand.
LOL this guys can teach flight mechanics to a toddler
Kazi Mehdi ikr!!!!!
You are not alone. This is what we call education for discovery.
Now i understand how USA got won WWII,they know what they do
Awesome video and very clear explanation
The explanation is very good.
Nice presentation.....very easy to understand...thank you Dana for uploading .
Well explained, Good!
I find non-digital technology way more fascinating than digital
Agreed
Superb Presentation...for understanding AM & FM..
I've listened to a lot of Radiolab in my time and I have no idea who's name this beautiful voice belongs to.
very very useful...Thanks a lot !!!
0:50 There is a mistake, the oscillator and the mic both feed the modulator and then the modulated signal goes into the radio amp.
TheDaniel366Cobra
yes u r right bro.
The carrier wave is modulated with respect to message signal in the modulator and then fed to the amp.
thank you very much for this video
Wow… thank you for this video.
I understand things much better now.
Peace peace peace
THANK YOU SOOOOO MUCHHHHHHHH THIS HELPED ME ALOT YOU SAVED MY LIFEEEE
excelent, thank you for you video
This is a very good film.
very, very good explanation
Beautiful
I love these old defence force videos
excellent explaination
I swear all the WWII to post war videos were narrated by this same guy. The funny thing is they all have good info
They need to make a video like this for machine learning.
Cool thing to do, Take the audio, put it in audacity, use the noise reduction by sampling the noise and then apply the reduction to the rest voila! It actually sounds good!
Modern tech is awesome!
Holy shit ! The best explanation (on Internet so far) ever !!!
Modern FM is a good deal more complicated than described here. The carrier is also modulated with subcarriers to carry stereo, SCA and RDS data. Many stations also transmit digital carriers for "HD"-channels although they are separate from the FM carrier.
Correct me ASAP if I am wrong: the electric signals are travelled into the transmitter where they are converted into radio waves. The conversion is done because of a process known as modulation whereby the amplitude of the wave is modified. Those waves are then known as carrier waves just because now they have modified amplitude. Those carrier waves travel through the antenna and later on reach the radio's antennas. Right?
If I am right then when are the radio "waves" actually made because isnt modulation when an existing wave is modified? So it's pretty obvious that the waves were made before modulation but how exactly?
Plz help I have an assignment to submit. Thanks
Woah! Nostalgic...
fascinating
The voice of this narrator is legit =)
great great video
i just finished building an AM radio from scratch. It was such a pain in the ass to built one
Wow!
Very nice
Best video
would you like AMMM or FMMMMMM
I feel like I got the reference, but I don't remember where I heard it...
@@phs125 mr mosely
Thank you
I did a one year long crash course in electronics for computers in 1979 (I was 6 months old when I took the course) at Career Learning Center in Toronto and this video brought all of that information rushing back. This great video, without intending to do so, explained single side band modulation too.
you took the course as a 6 month old baby?
Yup. I was an advanced child.
@@namename8986 i was already divorced when i was 6 months old. She took my 2 year old son too because the court said "i was too immature".
Description says this video is 'highly edited'. Is there an un-edited version?
I have my spiral bound copy of "An Inquiry Into Things Enigmatic". Nice to see you are still educating the unwashed masses. {former grunt for moses}. For those of you who think tech is for nerds, I can assure you that Dana's wife is the most beautiful woman I have ever seen. There I said it. We all worked in the same place in the 90s...
They sure knew how to explain stuff back then!
the education that was
You don't need fancy graphics and high quality cameras and beautiful/handsome faces to tell you about scientific concepts. These work better.
Still useful in 2020
cool!
MUITO LEGAL
Its a brilliant video - if you have learnt about waves and frequencies first
No hating
Loved it x
Sir add all the videos, y u stopped ur channel, so urs finest video I ve ever seen
ET3 IS A KURWIONE GUWNO
Is that Bing Crosby narrating this video? While I like the Voiceover guy that goes the voices for all those talk sports stations, I think this voice would be awesome for a serious news station like WINS or WCBS. By the way, the guy who does all those voice overs, has air checks of him doing top 40 radio in the mid-80s in Boston. I think it was WKKS?
Thanks
Would you like AM or FM?
I like AM, though I don't know why I like AM more.
Is 7:30 not incorrect? They mix up amplitude modulation with frequency modulation. Changing amplitude does not change the end signal in FM (they even filter amplitude variations later in the receiver).
No, it is correct. I think you might be misunderstanding the graphic. What it is illustrating is that higher amplitude of the input signal leads to a larger deviation from the rest frequency in the output signal. Its amplitude, however, is irrelevant, as you say.
I can imagine a classroom full of soldiers in 1940 falling asleep to this. This guys voice could use some modulation.
Travis Butler hahaha ... truly notes out
I suppose the guys (in 1964 by the way) who were not interested in electronics may have been uninterested...but I’ll bet a bunch of people learned a lot because they watched this little film.
full maza learing thank
any videos like this?
ch0bits You just watched a video. With audio.
Is this free stock footage?
Eric Mason Just google the title I have in the description for the full version. I believe it's basically in the public domain, as this was a US government film, and those are released...
+Eric Mason no, you must pay me
I wonder if Dolby noise reduction was based off the limiter. - Seems similar.
not really (at least I don't think so). Limiter when used drastically introduces its own artifacts like distortion which in effect is similar to hash itself. Now that won't be a problem in FM receivers since it only decodes data from the frequency information and the limiter only gets rid of the peaks. Even then the limiter is used only with certain preset settings so as to minimize risk of distortion since it's capable of adding additional harmonics meaning introducing frequency content, which is dangerous in FM. Here its only used to clip off the peaks and keep the signal uniform cuz what matters is frequency not amplitude.
The US Army is the best at explaining things! If only we had such good Education in Germany...
Guitar3000LP I hope my country survives Trump to be able to do good things like this again.
I REALLY wanna know how this motion graphic was achieved back then.
I don't know about this specific training film, but the US Government used to contract out a lot of animation work to Disney and Warner Brothers (the infamous Private SNAFU cartoons were made by WB). So, it is entirely possible that this training film came from either the House of Mouse, or Bugs Bunny land (the narrator even sounds similar to the one Disney used for the True Life Adventures series).
Sorry if i'm being stupid, I have my Electronics college exams coming soon, and am scratching up on some things learned a few years back, I assume that by "Kilo-Cycles" this also mean Kilo-Hertz? And vice versa for Mega-Cycle = Mega-Hertz?
Yes, that's right.
Ok, thanks for the quick response.
yeah of course. Hertz is a measurement unit for cycles (or frequency). Its like saying Distance and kilometers or miles are same (which they are).