modulation explained, with demonstrations of FM and AM.

Modulation is the way information is transmitted via electromagnetic radiation, like radio, microwave and light. This video introduces the concept of modulation, and includes demonstrations of amplitude modulation (AM) and FM modulation(FM)
The website I sue for the simulation - academo.org/demos/amplitude-m...
The light modulator can be purchased here - profbunsen.com.au/the-light-m...
the wavelab signal generator can be purchased here - www.iecpl.com.au
See www.physicshigh.com for all my videos and other resources.
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[@W8RIT1]

From my knowledge and education in electronics engineering and as an amateur radio operator this is an excellent video to illustrate modulation. I will share this with others to let you so aptly describe modulation so they can learn.

[@jbird7867]

That light modulator is so unbelievably cool!

[@bobwilkin5482]

I have searched high and low trying to understand modulation (I just bought a shortwave radio). This is the only explanation I found that helped me understand it. Great video!

[@christopher9727]

Jesus Christ is the only hope in this world no other gods will lead you to heaven There is no security or hope with out Jesus Christ in this world come and repent of all sins today Today is the day of salvation come to the loving savior Today repent and do not go to hell Come to Jesus Christ today Jesus Christ is only way to heaven Repent and follow him today seek his heart Jesus Christ can fill the emptiness he can fill the void Heaven and hell is real cone to the loving savior today Today is the day of salvation tomorrow might be to late come to the loving savior today Holy Spirit Can give you peace guidance and purpose and the Lord will John 3:16-21 16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. 17 For God sent not his Son into the world to condemn the world; but that the world through him might be saved. 18 He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God. 19 And this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil. 20 For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved. 21 But he that doeth truth cometh to the light, that his deeds may be made manifest, that they are wrought in God. Mark 1.15 15 And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel. 2 Peter 3:9 The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance. Hebrews 11:6 6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him. Jesus

[@aimortality5211]

carrier waves should be called "reference" wave. Would've saved me a headache. The receiver figures out how the reference wave is changed "modulated" over time and works out the signal wave. This was the best vid and explanation I've found on the net. Thanks.

[@yommish]

Yeah, the word carrier confused me into thinking I didn’t understand FM.

[@jaywitt5171]

I'm just delving into the shortwave radio world and have been looking for a clear explanation with demonstration of AM/FM. This was perfect! Thank you

[@PhysicsHigh]

Glad it helped. .

[@christopher9727]

Jesus Christ is the only hope in this world no other gods will lead you to heaven There is no security or hope with out Jesus Christ in this world come and repent of all sins today Today is the day of salvation come to the loving savior Today repent and do not go to hell Come to Jesus Christ today Jesus Christ is only way to heaven Repent and follow him today seek his heart Jesus Christ can fill the emptiness he can fill the void Heaven and hell is real cone to the loving savior today Today is the day of salvation tomorrow might be to late come to the loving savior today Holy Spirit Can give you peace guidance and purpose and the Lord will John 3:16-21 16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. 17 For God sent not his Son into the world to condemn the world; but that the world through him might be saved. 18 He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God. 19 And this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil. 20 For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved. 21 But he that doeth truth cometh to the light, that his deeds may be made manifest, that they are wrought in God. Mark 1.15 15 And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel. 2 Peter 3:9 The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance. Hebrews 11:6 6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him. Jesus

[@josstark8124]

Excellent demo. I now have a much better understanding. Thanks!!

[@jimmyjames_yt]

confusing, best explanation so far. thank you Paul

[@samuelholder5554]

this was really well done for most youtube videos thank you

[@VocalChainsStudio]

Amazing demonstration. Thank you🦑

[@jonasan77]

Incredibly good, thank you!

[@matheussalmaso6685]

This vídeo should have a lot more views! It is amazing. I wish I found it before! Great job

[@PhysicsHigh]

Thanks

[@michaelzlab]

Awesome! Loved it and great job!

[@EthanRMus]

Perfect video. Great job thank you so much

[@gnewdog4862]

Well done! Really cool light device, too!

[@brytpaipila1366]

Honestly you have opened up my mind on modulation ...Thanks alot

[@aprisonerscinemastephenmur6932]

This is the most amazing thing I’ve ever seen

[@anamark2854]

This was extremely helpful!

[@vyomab515]

Wonderful! Thank you!

[@lunyteve]

Very cool demonstration

[@Courtney0]

Wow! This has helped me tremendously. Thank you so much sir! Feeling more confident!

[@PhysicsHigh]

Glad it helped!

[@UsatMVS]

Great video, good job!

[@jamienoonan1186]

You're a wizard Paul. Pure magic!

[@PhysicsHigh]

Thanks

[@fazapops]

This is a great and fundamental demonstration. Thank you!

[@PhysicsHigh]

You’re welcome.

[@sameerlawande5701]

Awesome video - thanks so much

[@michaelk6140]

Tank You Very Much for this explaination!

[@emmanueladams419]

this is ultra comprehensive, now i don't have problem knowing how AM and FM work. thank u sir.

[@PhysicsHigh]

Thanks

[@Numocron]

Wow man this is such a great video I love it. :)

[@sweetumms5308]

Thank you!

[@neilz654]

Geat explanation!! Thanks

[@tito51rivera15]

For student like me is excellent video Thanks

[@johngreene6956]

Excellent, thank you

[@tuvelout]

really loved learning this stuff pr

[@paulvale2985]

Blinded by the Light by Manfred Manns Earth Band: Composed by Bruce Sprinstein. Now known as Transmitted by the Light by HSPE.

[@DarkbrainixSlickerTH]

Thanks. Very clear.

[@nasirnoori6864]

Amazing Info

[@PhysicsHigh]

Thanks

[@noduslabs]

Amazing devices! How can one make them or get them? :)

[@danmesserich8760]

This was very helpful. Your visual examples were great. I’m just getting in RF so could you put together another video on why we need to modulate the message? Maybe I missed it in this video.

[@PhysicsHigh]

Modulation means to change. It’s not the message that’s modulated it’s the carrier wave in such a way that carries the message.

[@homoevolutus]

A couple of reasons to modulate a higher frequency carrier wave would be to transmit the signal farther and also the antennas can be smaller. The higher the carrier frequency (the one you are modulating) the smaller the antenna can be. For example, a 1 MHz signal has a 1/2 wavelength (for dipole antenna) of 468 feet vs a 1GHz signal with a 1/2 wavelength of .468 feet (~14.3 cm). In his case the antenna is the size of light waves ... so, pretty small!

[@accumulator5734]

What modulation scheme does high bandwidth fiber transmission lines use? Is it QAM OFDM like cell towers and HFC plants are or is it something totally different?

[@Jude107c]

Where did you get the animation to explain AM and FM Modulation?

[@bertaga41]

I have been struggling to get a clear explanation of this.This is the best I've found so far. Can you suggest any scientists who discovered/ worked out the concept of modulation at its simplest level?

[@homoevolutus]

He has a picture on his site of Alexander Graham Bell transmitting data via modulated light waves from the sun in 1880. That seems pretty significant if nothing else.

[@troys6965]

KZbin Kathy Loves Physics. She often explains the thought processes, right and wrong, of the people behind the revelations in physics.

[@bertaga41]

@@troys6965 Thank you

[@brytpaipila1366]

i totally agree with you

[@g_pazzini]

easy to understand

[@searching010]

which software you use for showing amplitude modulation. If you like tou share such kind of free available software it would be great for us

[@gazzacroy]

cool video :)

[@mohammadfakherddine3747]

Hello while in FM. the frequency of combinations of carrier signal and source signal is changed allover the time how my radio can receive the source signal at one frequency? thank you

[@PascalGienger]

The superposition actually was used - to encode color on top of the luminance signal of television/video. The phase shift from the reference ("color burst") at the beginning of each video scan line was the tint/color, the amplitude of the added color frequency was the color intensity ;-) That's why old black and white televisions without a color frequency filter showed checkerboards and moirée patterns when receiving a color signal...

[@christopher9727]

Only Jesus Christ blood can cleanse us of are sins come to Jesus Christ today Romans 6:23 For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord. Come to Jesus Christ today Jesus Christ is only way to heaven Repent and follow him today seek his heart Jesus Christ can fill the emptiness he can fill the void. The Holy Spirit can lead you guide and confort you through it all Heaven and hell is real cone to the loving savior today Today is the day of salvation tomorrow might be to late come to the loving savior today John 3:16-21 16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. 17 For God sent not his Son into the world to condemn the world; but that the world through him might be saved. 18 He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God. 19 And this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil. 20 For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved. 21 But he that doeth truth cometh to the light, that his deeds may be made manifest, that they are wrought in God. Mark 1.15 15 And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel. 2 Peter 3:9 The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance. Hebrews 11:6 6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him. Jesus

[@Gigilonto]

Thanks!

[@PhysicsHigh]

Welcome!

[@robertsherertz]

That's awesome so is that song listen to it when you're really high

[@lewisrobson9414]

my mind has been blown

[@NotMarkKnopfler]

Blinded by the Light! 👍

[@wesKEVQJ]

Where do the sidebands come in?

[@NishantGogna]

This is great but how does the demodulator actually work? Like is there some sort of computer code involved? What’s the math to extract the signal?

[@Joe-li3zj]

If one hooked up an AM antenna, tuned to a specific frequency, to their skull or ear bone, they couldn’t make out anything intelligible, correct? They might pick up changes in amplitude, but without a decoder, couldn’t make out audio?

[@centraliafuckcorruption]

the link that sells the sound to light to solar panel to speaker link wont work, i would like to get one for my kid tia

[@aboukhaleed1340]

I want a video about dsb fm with the circuit that doing it

[@JulianJawadAhmad]

What software you used to show the animation?

[@PhysicsHigh]

Here you go academo.org/demos/amplitude-modulation/

[@madhureshminoshi4272]

thank oyu

[@NikErrant]

I was hit with some questions and this answered a whole lot of them. My last one is how advanced chips would you need to have in order for this to work. To me it seems like you need to do some math to undo the modulation and that sounds like it would need some kind of chip doing math to turn it back into what it originally was. Perhaps I underestimate the computing power of old first and second generation radios but I am looking for how that process works specifically

[@PhysicsHigh]

Yes. That’s what demodulators do.

[@philhoward4466]

how can i do FM over light?

[@mustafarasool7591]

thanks , what is the name of program you used to see the waves

[@PhysicsHigh]

See academo.org/demos/amplitude-modulation/

[@fibberscloset498]

In AM or FM, the source signal (sound) contains both volume changes and frequency changes. I've never been clear how AM or FM encode for both. Amplitude changes are kind of obvious, but frequency changes? Not so much. Does this have to do with bandwidth? How do two frequencies get modulated? It can't be just the amplitude of the carrier, can it?

[@troys6965]

If I understand correctly, in FM, the broadcast frequency is the center of a small frequency bandwidth. Within that bandwidth, the frequency (rate) of deviation of the center frequency corresponds to source frequency. The amount of frequency deviation from the center frequency corresponds to source amplitude. It helps to think of it in the frequency domain as well as the time domain.

[@troys6965]

KZbin channel Kathy Loves Physics.

[@IllidanS4]

Modulation is changing the property of one wave (the carrier wave) based on the *value* of another wave (the signal). The value of a wave as a function of time is the immediate displacement of the oscillator that produces the wave, but frequency or amplitude are properties of the whole wave, or at least a local region of it around a specific point in time. You don't need to "encode" properties of the function like the amplitude or frequency, you just encode the function itself, as variations in the amplitude or frequency of the resulting wave.

[@vultusalbus4216]

As an amateur musician, I refer to FM as Vibrato Broadcasting and AM as Tremolo Broadcasting

[@PhysicsHigh]

Love it.

[@paulsenjohannes]

Now I have a clear understanding of the basics of am and fm. Now to find a video that explains an electronic circuit of a transmitter that converts audio sound to am or fm.

[@linearz]

Did you find one?

[@stephanielefebvre4306]

Thanks good content recommend by Radio Amateurs of/du Canada (RAC) course. 💜🇨🇦

[@kenlansing1216]

Blinded by the Light.

[@aboukhaleed1340]

Sorry thanks for this presentation

[@dz-jw5dg]

But are there essentially two distinct photons (of distinct wavelengths) jumbled together (for AM)?

[@harrysmbdgs]

I came to ask my own question but this one really got me thinking! I may be wrong, but I believe the modulation is happening to the light output (voltage / frequency shifts), rather than the actual photons of light or the wavelength. Bear in mind that wavelengths of light are orders of magnitude shorter than audio / radio and shouldn’t be a factor when considering either of the modulation frequencies. Obviously more light means more photons, but my thinking is that the LED chip in the torch will naturally have its own combination of wavelengths being emitted, which the circuitry can’t control. I imagine this would vary slightly depending on the output power, ambient conditions, etc., but I don’t think a solar panel should be able to distinguish between these in such a manner. I think if our eyes were infinitely sensitive, we would be able to see the brightness of the light varying very slightly as the modulated signal is transmitted, in the same way many LEDs use PWM to effectively dim. If photons or the wavelengths of the torch light were being altered, the variation would be seen in the colour of the light, rather than the brightness. Again… I think! 😂

[@rileypatterson7512]

Why is it so interesting?

[@muhammedtalhayasar6687]

which app or website that u use to visualize the waves pls?

[@panagiotisk9670]

i use octave/matlab. Its excellent for analog and digital signals

[@muhammedtalhayasar6687]

@@panagiotisk9670 i'll consider, appreciate that

[@surendranmk5306]

What would you say when I told you that it is not amplitude modulation instead it is intensity modulation. C is all ways equal to frequency × wave length with any electro magnetic wave. Amplitude is strictly varying with frequency.

[@pedroferreira8600]

you saved me

[@jupitersaturnuranusneptune2816]

How is signal added to carrier wave? What exactly occurs in the spot where they are added together? Why does carrier wave change just because signal is added to it? What device is used to add the carrier wave and the signal wave together? What happens at the other end, how is signal extracted from the composite waves, how is done and by what?

[@MrPabloguida]

Yeah, this part could've been a bit clearer. Adding them up generates the wave that he said it was NOT a modulated signal. You, actually, have to multiply the two trig functions to get the modulated signal.

[@adeeljamal3309]

Any one want to chime in? What exactly is a signal. What exactly is a carrier wave. Vibrating air? Absorption/emission of an atom?

[@gabrielfalcao2952]

You guys really are going to need graduation in Telecom for that. Those answers answered in deep detail takes time to study and learn.

[@jupitersaturnuranusneptune2816]

@@gabrielfalcao2952 hello: Do you know how the modulation and demodulation work and why they work?

[@gabrielfalcao2952]

@@jupitersaturnuranusneptune2816 A bit. I'm still mid semester.

[@James_Earle_Fudge]

Pretty crazy how our brains have created all this in the 3D. The brain is making itself and continues.

[@shuckarooo]

what was that song tho?:D

[@PhysicsHigh]

Blinded by the Light by Manfred Mann's Earth Band

[@coochykilla]

3:25

[@ojas3464]

👍

[@florentinosanchez3969]

You need a picture of Nikola Tesla in your wall as well

[@PhysicsHigh]

I do!

[@user-zz2od5gc9e]

MODULE MODULATED SIGNALS IS LIKE FC UK STARBUCK KING HAM AND CHEEZY SQUEEZED BY FRENCH BIGETTE OH LA LA WAHAHHAHAHAHA

[@licence1001011]

❤thank you. And if anyone can contact me. I just staryed radios and need a few things figured out

[@starchild7843]

That speaker he showed in the beginning of the video looks like an old Atari paddle controller! That's what I thought that was for a split sec before he told what it was! ☺️ Makes me feel like a dummy a tiny bit!!🤪🥴🤭🙂🙃🙂

[@bramakumbara1185]

Now i get why arctic monkey album looks like that

[@muhammadm4582]

Modulated = superpositioned?

[@PhysicsHigh]

Not really. Superposition means the waves are added. In reality the source wave equation and carrier wave are multiplied though it’s a bit more detailed than that.

[@keylanoslokj1806]

​@@PhysicsHighhow more detailed

[@paulfrancis8836]

can't be clearer.

[@garymarullo]

Modem

[@edd189]

That’s not a torch, it’s a flashlight. Silly.

[@PhysicsHigh]

Torch on Australia 😀

[@GereDJ2]

Pronounces the word "Here" as "He".

[@vasile.effect]

Did Einstein understand how this amplitude modulation works ? Because his photon has no amplitude what so ever. It's just a straight line, or a particle-line as I call it. Funny that you have a poster of him, though. Maybe he finally learns his highschool lessons now.

[@vasile.effect]

You did not specify the flashlight modulator is AM or FM ? If it is AM, Einstein's photon makes no sense, because it has no amplitude what so ever. And it already did not make any sense, because a wave without amplitude is not a wave, its just a straight line. So his photon particle-wave is a particle-line.

[@unicornwithnohorn6230]

Tbh IDK about some of the things you mention, but my mind jumped to fiber optic cables. My imperfect understanding of fiber optic cables is that they use amplitude modulation to transmit information, while using different wavelengths to transmit potentially multiple data streams on 1 line. Because they transmit information with AM in fiber optics, it seems more likely to be AM here.