Thanks for this gift! Donations like this help us acquire, preserve and present more endangered films.
@davidryan672
Жыл бұрын
Back in the 70's, when I was an A/V tech at a local community college, I used a 16mm copy of this film as a test reel when repairing Bell & Howell movie projectors. I watched it at my bench, countless times on a piece of 8.5 x 11 cardstock for a screen, learning about frequency modulation in the process. Years later I applied for and got my FCC GROL and thanks in part to this film I got through the FM questions without trouble. Never knew of Kent Smith except for this film until later I saw him in several movies. I couldn't look at him in a movie plot without thinking of his voice saying "the capacitance of the tank circuit affects the frequency of the oscillator". Thanks Periscope for preserving these valuable historic treasures.
@mistergrandpasbakery9941
Жыл бұрын
Nice!
@Kangaroojack1986
Жыл бұрын
These old movies seem to be much better at explaining basic principles of complex topics. Check out the early GM films about differentials for a perfect example of this.
@jharris0341
Жыл бұрын
@@Kangaroojack1986 Dude, that GM film is awesome.
@jaysonscott187
Жыл бұрын
Thats beautiful, man. Thanks for sharing
@Locutus
Жыл бұрын
70s, not 70's. Seventies, not seventie's.
@FrypanMan69
Жыл бұрын
These old videos are better than any college lecture I've ever attended
@Otswartz
Жыл бұрын
Just think of all the money you could have saved ! :)
@JKGrimm
Жыл бұрын
I swear I'm learning more from these than anywhere else
@penatoliy
Жыл бұрын
I can say same for some ussr education videos.
@VintageAviation737
Жыл бұрын
That’s what I’m saying duddeeee. I find myself understanding better when I watch videos like these
@complexity5545
Жыл бұрын
I wish I could find a library with all those 1940's and 1950s education and military videos.
@vancouverman4313
Жыл бұрын
These old training films are so well explained that anyone could understand them. Kent Smith, the actor who is doing the narration and demonstration was in the late 1960s science fiction program, The Invaders. He played the multimillionaire government contractor who was sympathetic to the main character, played by David Thinnes, who financed him and gave him contacts in the US government.
@curtislowe4577
Жыл бұрын
I thought he looked familiar. I'll have to research if he guested on Perry Mason.
@Col_Sanders
Жыл бұрын
And it's not like basic understanding of AM/FM has changed. This video is every bit as relevant today as it was 80 years ago.
@bringer-of-change
Жыл бұрын
I strongly agree.
@navizhunastye3756
Жыл бұрын
Ну вот и ему достойное место в истории развития радиосвязи подкинули. Дрочи дальше.
@MrBonger88
Жыл бұрын
You got the names mixed up. Easy mistake. It was Roy Thinnes who played David Vincent. Thanks , I was trying to figure out why Kent Smith looked so familiar
@HogTieChamp
Жыл бұрын
I love the fact that he uses the term 'hashing up' or 'hash up' to refer to the introduction of a second pattern (noise, in this case) to the encoded / modulated "intelligence" signal. The modern use of 'hashing' relates to the introduction of a second pattern -- usually an encryption code -- to modern digital intelligence. At heart, these two senses of "hashing" are identical, even while the carrier of intelligence is different. I love it because most of the concepts and terminology of modern computer science actual _pre-dates_ computers themselves! The modern conception of using strings of 0s and 1s as carrier of information is just a re-envisioning of the early 20th century technology of analog electrical pulses or radio waves as a carrier of information. Very cool!! 😀
@knighthawk2062
Жыл бұрын
This is amazing and you are amazing... Thank you!!! Love learning 😂😊👌♥️
@shroud1390
Жыл бұрын
How are they actually sending 1s and 0s? If you look at digital AUDIO its almost always an analog carrier wave, usually voltage. Where the voltage is read as a 1 or 0.
@HogTieChamp
Жыл бұрын
@@shroud1390 I don't know enough about the technical details to give you a complete answer, but I'll share what I know. There are many methods to modulate a radio signal to carry 1s and 0s. Amplitude modulation is probably the most familiar because it maps nicely onto that voltage modulation strategy you described. Instead of high/low voltage, the radio waves are "burst" in chunks of high or low amplitude. Even more simple is OOK modulation, meaning On-Off Keying, where the high-amplitude signal is literally switched on for 1s and off for 0s. (OOK is crappy because a string of 0s is just dead air, so the signal falls apart with even small noise.) There is also frequency modulation that works exactly like the analog FM described in this old video. Instead of having smoothly-variable frequency modulation to carry an analog message, the frequency is "jerked" back and forth to represent only two distinct values. (I think that's how those FRS "walkie-talkie" radios work, but I'm not certain.) There are several other modulation methods, like "side-shift modulation" and many others, but to be honest, I don't understand how any of that works. Bluetooth and WiFi use some pretty amazing modulation methods that permit sustained high-bitrate throughput even with dozens of devices blasting away. "Frequency hopping" is a big part of the solution here. All of it is interesting, but I don't claim to understand how it works.
@Professor-Patti
Жыл бұрын
Yes, the more things change the more they stay the same & there is nothing new under the sun. As a tenured computer professor, I totally & completely validate your comment. I often think how funny it is that all the answers, all the technology has been here all along, it's us humans that had to catch up or realize it. Wonder what else is around that we don't see yet? Great comment @HogTie Champ and what a great name, too.
@Professor-Patti
Жыл бұрын
@@HogTieChamp It is very interesting and though I was tenured in Computer Science & taught the basics the science is still incredible and quite in-depth. Lovely, intelligent comment ...again!
@I-Libertine
Жыл бұрын
These are so well done because the stakes for failure to communicate vastly exceed the self-absorbtion of the speaker.
@cjay2
Жыл бұрын
At 3:24 the film has the MODulator and the AMPlifier functions reversed. The film's 'MOD' is the audio amplifier and the film's AMP is the modulator stage.
@mjkirk12
Жыл бұрын
I noted this also. And there usually is an RF power amp after the modulator feeding the antenna.
@tomstrum6259
Жыл бұрын
No,.Per U.S. Army, the film is correct.......Back in those times, the Modulator block contained All the Audio amplification circuitry.....The Critical frequency stabilized Oscillator was physically Separated from the Rf Amplifier, which the Modulator is wired to.....
@official-obama
Жыл бұрын
@@tomstrum6259 still, the modulated signal is over the amplifier
@eltrylogis
2 ай бұрын
We have to see how was made some electronics in these times, maybe inside the box are the circuits amp y mod
@avalanche9026
Жыл бұрын
The generation that changed the world. May rest in piece
@mandarbamane4268
Жыл бұрын
All generations gave some contribution. Fourier and Laplace are also important people
@johnnywood8371
Жыл бұрын
As a professional guitar player who uses a compressor (sometimes called a compressor/limiter), this is the best explanation I have seen for what it does. Compressors are used widely by individual musicians and in the recording studio in post-production to make a signal more crisp and clear and somehow fatter, fuller, and punchier. Unlike distortion, delay, reverb, etc., this effect is the hardest to understand or describe. Since I got my first compressor/limiter many years ago, it has been my desert island effect. More than overdrive or any other effect, I cannot go without it.
@morbidmanmusic
Жыл бұрын
It's not that hard to understand.
@datboib3432
Жыл бұрын
@@morbidmanmusic he didn’t explain how the compressor works, just how it’s utilized by musicians. Which is useful for somebody who isn’t a musician, or a novice musician. Unless you know what to listen for, the average person is not going to hear the difference that a compressor makes. But its very easy to hear what reverb, or distortion is, as was explained by the original poster. He also didn’t say he was confused by it. Rather, he explained the ways he likes it, and why he uses it. Your comment was only a few words, but it was chock-full of poor reading comprehension. Your ego got in the way, for literally no reason
@nap871
9 ай бұрын
Can you play freebird
@taymur0804
Ай бұрын
This puts me on mind of the luminance signal of VHS which uses the FM, this was an easy presentation to learn.
@kkampy4052
Жыл бұрын
My dad ran FM repeater stations out of a tent all over Europe in WWII. He was in the 926th signal batn. Part of the 9th TAC.
@karlbergen6826
Жыл бұрын
This film is easier to understand than anything I've seen on FM. Even now technically useful.
@navizhunastye3756
Жыл бұрын
Ты принцип работы транзисторов в школе не изучал?? Пичалька...
@davidechiappetta
Жыл бұрын
Kent Smith I have seen in many films, but what I will always remember are the two masterpieces 'Cat People' and 'The Spiral Staircase', flawless as always.
@aprylrittenhouse4562
2 жыл бұрын
No. Silly me. That was awesome. I never knew how much went into this. I never knew how fm got rid of the static. Amazing how they invented this stuff. Thanx
@PeriscopeFilm
2 жыл бұрын
Love our channel? Help us save and post more orphaned films! Support us on Patreon: www.patreon.com/PeriscopeFilm Even a really tiny contribution can make a difference. Subscribe! Become a channel member kzitem.info/news/bejne/sHp4vWemj5OZiHo
@ranjeshkumar6799
2 жыл бұрын
@@PeriscopeFilm श
@jessihawkins9116
Жыл бұрын
@@PeriscopeFilm how tiny?🤔
@Locutus
Жыл бұрын
Nothing really amazing. It's just physics.
@jessihawkins9116
Жыл бұрын
nobody hear invented anything it was taken from Germany at the end of ww2 or the guvment got it from the grays
@NipkowDisk
2 жыл бұрын
Somewhere in the bowels of my house I have a circa 1941 book titled "Understanding Radio". It referred to FM as 'static-less radio' and essentially said it was revolutionary. Looking at FM today... indeed.
@metalbill
2 жыл бұрын
Nowadays, Commercial FM radio is full of more noise than ever!!
@rawcado
Жыл бұрын
@@metalbill These days only old farts say Now-A-days 😆
@ChipEckardt
Жыл бұрын
These old military educational videos are AWESOME!!!
@PeriscopeFilm
Жыл бұрын
Thanks @Chip Eckardt. Please consider subscribing or become a channel member!
@navizhunastye3756
Жыл бұрын
Бесшабашны и бесполезны точнеее.
@misterdeplorable2088
Жыл бұрын
@@navizhunastye3756 isnt there a tide pod somewhere that needs eating ?
@Jeru185
Жыл бұрын
They don't make them like that anymore - absolute gold!
@f1r3hunt3rz5
Жыл бұрын
Some things in the old days were simply just better, no questions asked, and these videos are one of them.
@Brad-qw1te
Жыл бұрын
3:50 I think an important thing that wasn't mentioned is why you need to modulate the wave. Its like putting a message in a bottle and letting water waves carry it across the ocean, only that here the ocean is the oscillating wave (An electromagnetic wave of some specific frequency) and the bottle is the sound signal you are trying to send. The oscillating wave is the medium where we can put out message and it can then travel wherever we need it too (within a range).
@alfonsonishikawa
Жыл бұрын
I asked my physics teacher at university how a FM receiver works and he couldn't explain it... This videos are gold, what a very good explanations! Thank you very much!!
@keylanoslokj1806
9 ай бұрын
They are way too bothered with theories and formulas to dedicate time to real life engineering
@nap871
9 ай бұрын
Can he screw in a light bulb or cut the grass. I personally know many lawyers who never had an original thought.
@komalvenkatesh4527
Жыл бұрын
It's old life changing educational content like this that makes you really doubt the current quality of school/univeristy education. Time and again, I always resort to these videos for clarity.
@arampak
2 жыл бұрын
There are a couple of misconceptions in the film. First, the lightning does not alter the existing wave. It does, however, complement the signal at the receiving antenna, as any other noise, as noise has a wide band and thus gets received by the radio tuned to almost any frequency in the wide range. Secondly, while talking about benefits of FM, it's important to talk about its major drawback, that prevents it from being used at critical settings: while an AM signal being dirsupted by a noise, static or other signal could still be perceived by our ears and brain in rather harsh conditions, the FM signal in the same situation will not even get into our ears at the first place. If two FM transmitters are tuned to the same frequency or their transmission bands intersect, their frequencies will get added or subtracted due to the interference effect, with arbitrary phase shifts, and the discriminator will not even detect a signal, just a noise in the best case. That's why FM is not used often in aviation, for instance or in any other situation when two sources may be unaware of each other and may want to transmit at the same time.
@ki4clz
2 жыл бұрын
To solve these problems, we use sideband... one, the bandwidth (what the officer refers to as deviation) of the signal is greatly decreased over FM and AM... two the Signal to Noise ratio is decreased... horray...! and three, with a "smaller" signal in use with Sideband we use less power... over simplified of course
@comment8767
Жыл бұрын
@@ki4clz You must mean that the S/N is increased.
@marcd1981
Жыл бұрын
Another issue with FM is that it is line-of-sight restricted when used for two-way communication radios. FM frequencies are in the VHF band range, which is limited by line-of-sight, and that is why for overseas / international travel, aircraft are equipped with HF radios to communicate with.
@DellAnderson
Жыл бұрын
Not an engineer so what you say may be true, but remember the audience for this film was military recruits with very little knowledge about FM. Excessive detail almost always confuses and frustrates the beginner detracting from the learning experience. Heard it said once that good teachers always lie, because EVERYTHING you say can be untrue under some circumstances, and has exceptions, caveats, and edge cases which if discussed in a first lecture would hopelessly tangle the beginning student up in confusion so deep they would throw up their hands in despair. To speak clearly and simply, one must almost always oversimplify. Then once the mental 'hooks" are created on which to hand key information, you can hang additional facts or exceptions without confusing the student. Hopefully you are not an instructor that likes to bamboozle your students so you can impress them with your brilliance or the complication of the subject. I assume you are aware of this teaching technique and were simply adding to the discussion rather than critiquing the teaching film for starting with the basics.
@wtxrailfan
Жыл бұрын
Hey, Sparky, it's a basic film to teach a basic concept to beginners; not to hash out every minute detail about the pros and cons of FM.
@RugNug
Жыл бұрын
That was cool. I was a radio guy in the Army 30 years ago, and believe it or not, some of the radios I worked on still had tubes.
@joehead1294
Жыл бұрын
I was a WCS radar tech in the Air Force 40+ years ago and the radar package I worked on was loaded with them.
@stevesilsby5288
Жыл бұрын
Montgomery Ward (remember them?) was still selling tube-type televisions through 1974. They had a big sale in our local store to liquidate the last of their stock of them that year. All of their models from 1975 on were transistorized, except for the CRT of course.
@complexity5545
Жыл бұрын
I have an piano organ that still has tubes. I bought a joe meek tube amplifier in 2010. Tubes add that pretty noise that sounds good when singing. I have a tube radio local broadcaster (which might be a little illegal if I push the wattage up). I wish I had your knowledge. Thanks for your service.
@ItsMe-vg4vj
Жыл бұрын
Tubes were used in communications amplifiers in early coaxial cable systems. Early 80s.
@SkyeMpuremagic
Жыл бұрын
This is so fascinating to me I've watched it twice and plan to watch it again another day. I love the illustrations in it... Makes everything so clear to understand. I remember being a kid wondering how this worked.
@lquinn7212
Жыл бұрын
Say what you want about A.M. radio. When we were kids my dad gave us old transistor radios. I'd lie awake at night tuning in stations hundreds of miles away.
@ryanhuang8498
Жыл бұрын
Both have pro and cons. In Taiwan,most people live in tall apartment blocks. So MW or AM is often very tricky to get signal due to multipath and interference. If you are out in the open AM or MW would work better because it doesn't rely on line of sight.
@benzflynn
Жыл бұрын
Considering it was 1944 I think this is a great presentation. Full credit to the US Army for being progressive in its teaching practice. A good-humored and clear presenter and state of the art graphics.
@skipmars7979
2 жыл бұрын
FM Stereo came out later for commercial broadcast. I believe it is on the other side of the resonate freq. shown at the 26:00 area of the video. This gives the dual channel stereo sound. That's why your broadcast stations are so far apart in freq. as opposed to commercial AM broadcast.
@michealobanaghan4220
Жыл бұрын
FM stereo transmits the sum of both channels at the regular audio frequency but then the difference between them outside the standard audio range - the receiver also detects the difference and then subtracts that to recover the two separate left/right channels. The difference centres around 38KHz, which is inaudible to humans and so doesn't interfere with mono
@colvinator1611
2 жыл бұрын
Excellent video! A nostalgic trip down memory lane back my army days at the School of Electronic Engineering in the early seventies.
@navizhunastye3756
Жыл бұрын
Сочувствую. От вас скрывали радиопередатчики AM, FM, SSB😂😂😂
@rachelcody3355
Жыл бұрын
I'm just starting to learn Ham radio. Thank you for these films. these are awesome and helpful.
@simonek507
4 күн бұрын
Amazing how much casual table tennis has improved since that time.
@nakayle
Жыл бұрын
The sound track is amazingly quiet for a 80 year old film even when there are visible scratches in the picture. There must have been some fancy processing done.
@FayazAhmad-yl6sp
Жыл бұрын
I studied AM and FM during my diploma of Radio electronic associate engineer back in 1979.
@Chris_at_Home
Жыл бұрын
Did you work in that field after you graduated?
@FayazAhmad-yl6sp
Жыл бұрын
@Chris Yes, i served in Pakistam television, worked on low and high power Transmitters, my specialisation was repairer and maintenance of power supplies and RF amplifiers.
@willthomsen7569
9 ай бұрын
It’s so amazing we figured all this out. Imagine discovering something THAT big :O
@sapper82
2 жыл бұрын
FM in the UK was referred to VHF, Very High Frequency.
@russnixon6020
2 жыл бұрын
VHF refers to the frequency of the AM carrier or the center frequency of the FM signal. FM modulation can occur anywhere in the RF spectrum. As a counter example, the VHF communications that aircraft use to speak to ground stations such as approach control is a VHF AM signal. As it happens, commercial FM broadcasts occur in the VHF portion of the radio spectrum, from about 50 MHz to about 300 MHz.
@sapper82
2 жыл бұрын
@@russnixon6020 During the '50s & '60s domestic radio sets in the UK would have a choice of VHF, Short Wave, Medium Wave and Long Wave as band selections until the American terms AM & FM came in.
@scottkasper6378
2 жыл бұрын
Yous also eat beans for breakfast
@russnixon6020
2 жыл бұрын
@@scottkasper6378 So enlightening...
@chris_vandepeer
2 жыл бұрын
@@sapper82 You can have AM or FM in the VHF spectrum "30 MHz to 299 MHz" . VHF only means Very High frequency.
@josemiguelmunoz6985
Жыл бұрын
This is, by far, the best and the funniest explanation of FM I've ever seen. Thank you!
@dorol6375
Жыл бұрын
This is the best??
@josemiguelmunoz6985
Жыл бұрын
@@dorol6375 The best and simpliest I've ever seen.
@seanj1984
Жыл бұрын
I loves these old training videos brings back memories
@abdulhakimlukwago88
4 ай бұрын
So for the best I've watched for explaining FM. Thank you
@doorvavaidya6961
5 ай бұрын
Better explained than my engineering professor. Thank you!
@jaldav
Жыл бұрын
Made possible by Edwin Howard Armstrong in the early 30s.
@Whowhatwherewhy
Жыл бұрын
Excellent videos. So much tech came from military applications we still use today.
@Professor-Patti
Жыл бұрын
Wow! I know this is a War Dept. film, but I am still struck with surprise when I heard swearing from a 1940s film, regardless of military men. This is a great training film, however. It's not like the information has changed over the past 80 years. I ❤❤this channel, it's a new surprise every day.
@nobodynowhere7163
Жыл бұрын
Amazingly simple explanation! These people were geniuses!
@ON5ALE-Alessio
Сағат бұрын
Wow. Thank you ! Thank you sir wherever you are !
@debeerpaul
Жыл бұрын
This is an 80 year old video/film. Simply amazing!
@anands6127
Жыл бұрын
Didn't not searched for it but was Worth watching it.Never thought science behind FM may be so interesting.
@akashverma5756
Жыл бұрын
Without computer and graphics, They made excellent and comprehensive video explaining working radio.
@manhoot
2 жыл бұрын
This certainly "tuned"me in to be what matters in life
@SoapinTrucker
2 жыл бұрын
A tuning circuit is a whole different animal ;)
@manhoot
2 жыл бұрын
@@SoapinTrucker I know you can tune a piano but you can't tuna fish
@DursunX
Жыл бұрын
i started my apprenticeship as a Radio Mechanic in 1994... that course shaped my path into an AV IT Electronic Technician. i wish we had access to material like this video as apposed to an old grumpy college teacher with a severe speech impediment.
@sandplt
Жыл бұрын
We are going away from basic science, we only see applications, this video is so wonderful because he explains basic principles here, so nice, pleasant
@drtidrow
Жыл бұрын
3:32 Somebody goofed when they put this together - the _modulator_ is where the carrier and signals are mixed together, though often the amplifier and modulator functions were done by a single tube.
@lp-xl9ld
Жыл бұрын
Thank you, Edwin Howard Armstrong! (the guy who invented FM)
@jharris0341
Жыл бұрын
I could watch these all day.
@ZaphodHarkonnen
2 жыл бұрын
Ohhhhhhh, that would explain why we moved most everything from AM to FM. I had always wondered why there was such a shift.
@jayrogers8255
Жыл бұрын
Except for aviation, in which you want to hear a weaker station if it’s in an emergency situation. Aviation is still A.M. to this day. Also, some hams use it, & C.B..
@captainkeyboard1007
2 жыл бұрын
The United States War Department delivered a science class lesson that would likely be taught in college.
@ckkmanltj
Жыл бұрын
My telecom and electronic training in the Air Force taught me a lot of the stuff and I still have a job almost 40 years later in the same industry. I do a lot more software than electronic nowadays though.
@alexyo2440
Жыл бұрын
When times are tough, the bankers need safety so they pay for quality war videos
@captainkeyboard1007
Жыл бұрын
@@ckkmanltj Thank you for tapping or typing to me.
@captainkeyboard1007
Жыл бұрын
@@alexyo2440 I thank you for tapping or typing to me.
@captainkeyboard1007
Жыл бұрын
@@alexyo2440 Thank you for tapping or typing to me.
@DK640OBrianYT
2 жыл бұрын
First, this is so perfectly explained, that even my dear old Grandmother could understand it. Secondly, it's also easy to understand why hash is called hash. It hashes up the mind and personality, which is absolutely correct. Excellent educational piece of filmstrip. Highly appreciated.
@stevesilsby5288
Жыл бұрын
As my ham radio Elmer told me, "The difference between AM and FM modulation is 90 degrees."
@slainesmith
Жыл бұрын
Splendid. Keep them coming. Looking forward to some 60's technical films.
@gcr1
Жыл бұрын
Ron Hinze. Call sign. KBOWAR. My late Stepfather. Was contracted to work at Area 51 back in the day. He would not talk about it at ALL!! R.I.P.
@user-rq9po2zv4k
Жыл бұрын
Це дуже важливо знати, дякую вам за працю
@flyingfortressrc1794
2 жыл бұрын
Wow that's some great information. Thanks for posting.
@PeriscopeFilm
2 жыл бұрын
Glad you enjoyed it. Love our channel? Get the inside scoop on Periscope Film! Support us on Patreon: www.patreon.com/PeriscopeFilm
@majoroz4876
2 жыл бұрын
Went through AF electronics school in '58. Standard text was AFM 101-8. We also had a BUNCH of these old movies. Wound up teaching it........then got a BSEE......taught more.....MS......then transistors, IC's, chips.......PhD in education.....ran the department.......... And retired. Ah........history,.
@iznasen
3 ай бұрын
What a manner of teaching
@ianashmore9910
Жыл бұрын
Many thanks to Headly Lamar.
@ChristCenteredMinist
Жыл бұрын
In the AM diagram, Amp and Mod boxes are switched.
@deniskhakimov
Жыл бұрын
After watching this fragment, I immediately went to the comments section to see how many users noticed it 🙃
@PfjAzSDRHBeternSFsCPjUrkzKWWSb
Жыл бұрын
I cant give a like or don't see . !! Whatever who you are .. What you think doing You just give me best and special lesson more than ideas... ❤🎉 Bless bless
@ronaldjorgensen6839
Жыл бұрын
thank you been waiting for more fm history
@Enigma758
Жыл бұрын
Just like that Steely Dan Song "FM, no static at all"
@SquallSf
Жыл бұрын
Thank you for preserving this and sharing it with us - people not being born at that time or lived in that place. I'm astonished by the quality of the video, especially the animations illustrating the point. How were these animations done in 1944?
@SavageOne420
Жыл бұрын
Animations were done one frame at a time and overlayed on the film
@SquallSf
Жыл бұрын
@@SavageOne420 That is a lot of work! Even more respect for creators of the video!
@sj6986
2 ай бұрын
I think this older video does a much better job of explaining FM vs AM because it first explains the problem that AM posed (although is skips over some problems like AM requires a lot more power to get the message across the same distance etc). The fundamentals of presentation haven’t changed and probably never will. You need to first explain what is it that you are trying to solve and why should the audience care. That engagement helps the audience understand the “how” in the middle. And then you finally, re-affirm the solution. Do not follow this simple recipe and then it doesn’t matter how smart or technically detailed is your solution, it is very hard to put your point across.
@plasticinthetree4261
2 жыл бұрын
Hey! It's our guy. Kent Smith! Peter Keating from the movie The Fountainhead. Awesome.
@HistoryandFacts
Жыл бұрын
Very informative
@pew8208
Жыл бұрын
i love when its explained very well by a man..
@TheDutchGuyOnYT
Жыл бұрын
Now I understand it more clearly
@dell177
2 жыл бұрын
I watched this film when i was goint to school at t Monmouth back in '67.
@balnc
Жыл бұрын
Finally, now I understand audio a lil better
@tylerarrigoni7700
Жыл бұрын
Great video....these old videos are so clear and well done.
@sherpempiric
Жыл бұрын
Ошибка в схеме с 2:58 минуты. Надо поменять местами усилитель и модулятор! Error in circuit from 2:58 minutes. It is necessary to swap the amplifier and modulator!
@KeritechElectronics
2 жыл бұрын
Ha. Found a WTF moment around 2:45: when explaining the AM principle of operation, they confused the AF amplifier with the modulator.
@jesseharriott4253
2 жыл бұрын
that guy made me laugh with the static joke, and then i couldnt help thinking a dead guy made me laugh.
@joshuablanton3016
2 жыл бұрын
I don't think so - I believe that the terminology used is correct. The "modulator" modulates the plate voltage of the amplifier (at audio frequency), which produces the AM signal. The amplifier is actually unchanged (design-wise) from a fixed-gain amplifier - if you vary its input power supply voltage, you vary its output gain.
@kenmore01
2 жыл бұрын
@@joshuablanton3016 No, he is correct. They confused the two. The "amplifier" amplifies the audio signal and the "modulator" modulates the radio wave.
@ScottGrammer
2 жыл бұрын
I saw that. I think it's just a jargon issue. In a classic AM transmitter, the audio from an audio power amp is passed through a transformer whose secondary is in series with the power supply of an RF amplifier. This modulates the power supply voltage of the RF amp and this varies its output in step with the audio.
@quantisedspace7047
Жыл бұрын
That's what I thought. The modulating signal goes into the modulator, which then 'modulates' the amp's output, according to the diagram. This means that the modulator doesn't really do much, and the amplifier has a sort of volume control, driven by the modulating signal. Nowadays, we consider a modulator to take two signals and produce an output that is a math function of the two. This film is obviously using the word as meaning something that takes a signal input and converts it into a form suitable for modulating. Yes, it's clumsy, but I can see how terminology could have changed over the years.
@mahyar305
Жыл бұрын
Incredible presentation for its time.
@kongol5036
Жыл бұрын
Why are these old videos so much better at teaching and explaining than the new shit we have in schools
@metalbill
2 жыл бұрын
Nowadays, Commercial FM radio is full of more noise than ever!!
@silverhammer7779
2 жыл бұрын
Most of that noise is the programming, not atmospherics 😉
@rawcado
Жыл бұрын
These days only old farts say Now-A-days 😆
@alimukhtar4759
9 ай бұрын
Very well explained❤
@negry_
Жыл бұрын
this is better than my university...
@mrshodz
Жыл бұрын
Great explanation.
@alanroche3872
9 ай бұрын
Whoa! The guy from the Time Tunnel! 😱
@felicciasc
Жыл бұрын
And 78 Years later, the FCC approves FM for CB Radio.... 40kHz is some good bandwidth there! Those must have sounded great.
@prabhakarv4193
2 ай бұрын
Very nice and informative
@tareksma1
Жыл бұрын
Thanks. I realy understood it now. Thanks for sharing
@joselino4813
Жыл бұрын
Excelente esse vídeo, é triste só velo 50 anos depois.
@hvcomputech
Жыл бұрын
In the 80s I listened to FM radio and every time I turned a fluorescent light on or off I could hear interference on the radio from the ballast. Where was the discriminator then?
@bringer-of-change
Жыл бұрын
This was an outstanding presentation.
@gneuhaus8047
2 жыл бұрын
Basic electronics lessons 1972 Fort Bliss, Texas.
@Jeremy.Bearemy
Жыл бұрын
0:57 I miss the days when "Are you silly?" were serious fighting words
@metroidragon
Жыл бұрын
3:22 "the electrical energy goes into the modulator, where it's amplified, it then goes into the amplifier..." lmao
@kevinmassey1164
7 ай бұрын
The fact I’m watching this on my super computer phone doesn’t escape me
@kamleshchavan7451
Жыл бұрын
Awesome video ,explanation is awesome , Do you have More video's on RF CIRCUITRY . Remote Control circuit's etc
@stevesilsby5288
Жыл бұрын
The audio from 4:30 to 4:55 was removed. The script's explanation of what the mixer and RF amps do must have been embarrassingly inane.
@spacebatstuckonearth8888
Жыл бұрын
All the amazing technology were build bac k in the day. THIS IS OLD BUT GOLD.
@TheOriginalJphyper
Жыл бұрын
I love these old informational videos. This one however, has proven to be too technical for me. I managed to keep up until about the 2/3 mark, at which point, things started going over my head. I never was able to wrap my head around circuit diagrams.
@KwasiuYasiu
Жыл бұрын
This is super impressive how they were able to do such videos that many years ago
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