modulation explained, with demonstrations of FM and AM. 

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

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

Glad it helped. .

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

Thanks

Glad it helped!

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You’re welcome.

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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.

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!

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.

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

@@troys6965 Thank you

i totally agree with you

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

Welcome!

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

Yes. That’s what demodulators do.

See academo.org/demos/amplitude-modulation/

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.

RU-vid channel Kathy Loves Physics.

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.

Love it.

Did you find one?

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! 😂

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

@@panagiotisk9670 i'll consider, appreciate that

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.

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

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

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

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

Blinded by the Light by Manfred Mann's Earth Band

I do!

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.

​@@PhysicsHighhow more detailed

Torch on Australia 😀

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.