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- Опубликовано: 26 окт 2018
- Today we will talk about two modulation methods in a radio field: Amplitude modulation (AM), and Frequency Modulation (FM): How they work, their differences and their applications.
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The most simple and clear explanation on internet. You are a gifted teacher. Majority on here it's just garble..garble...garble only they understand. New subscriber.
Mr Sunny, you are got full respect. you make it easy on the eye!
This is a great video. Well done. Learned lots.
Awesome lecture Sunny...!!!
🏅🥇!!!
Thank you sir for clear explanation
Thanks Sunny. It's a wonderful lecture.
Sunny you are so helpful. thank you!
Sir absolutely helpful video
But also add phase modulation and also the mathematical theory aslo
Sir your explanation is very well please make a video on delta modulation and differential pulse code modulation.
Thanks, Sunny.
That is nicely video thank you so much
Thank you, Sir !
Very helpful..
Thanks for this
Thank you for making this video. It's so helpful.
You are welcome!
Thanks for the video. Why is the frequency not affected? I can't find any resources that connect this topic to basic wave interference in physics.
thank you so much, what a great video!!!
You are so welcome!
Thank you Sunny for your excellent lectures!! In your previous lesson, you said carrier waves travel further than signals because they have higher frequency . Does it mean higher frequency waves have larger area coverage? IF SO, but in this lesson you said AM covers larger area because of its lower frequency! Do you mean , in general, carrier waves used in AM have a lower range than carrier waves used in FM? Thank you
carrierwaves do not travel further than signals. In fact, some radioamateurs use signals without carrierwave to get greater distance. It is called "single side band", either upper or lower. (SSB, USB, LSB)
Higher frequencies don't have larger coverage, but in shortwave they do have a bigger "dead-zone")
I LOVE THIS
WOULD YOU LIKE AM OR FM??
It depends. AM is cheaper and transmits over longer distance, but with noises and lower quality. FM is in high quality, but expensive and transmit over the shorter distance.
@@sunnyclassroom24 sir, example if i am using a transciever radio @27Mhz FM and my friend i using a transciever @27Mhz AM, can we talk to each other? or can we hear each other?
@@neildelacruz6643 maybe not.
@@sunnyclassroom24 thank you sir for the reply..i am learning from your videos..
@@neildelacruz6643 You are welcome!
Very interesting, thanks. :D
You are welcome!
great video!
thanks a lot for leaving nice comment.
thanks prof
Well explained
Thank you for watching!
hi sir, which tool you use to make these video
On FM, if the frequency is changing depending on the data signal, how can a radio receiver tune to that carrier frequency? Does frequency modulation actually change the carrier frequency?
Yes, on FM it changes carrier frequency up and down from main tuned frequency and it is called bandwidth. There is narrow bandwidth and wide bandwidth. Narrow bandwidth is used for voice communication where is not important complete audio spectrum such bass and treble audio frequencies like on police, army, fire department... communication so the bandwidth is narrow and it could be 30kHz, 25kHz, 12kHz, that means on 30kHz bandwidth it changes 15kHz up from main frequency carrier and 15kHz down from main carrier frequency, on 25kHz bandwidth it changes 12,5kHz up and 12,5kHz down, on 12kHz bandwidth it changes 6kHz up and 6kHz down from main frequency carrier. The narrow the channel bandwidth is the lower the quality sound reproduction is (cutting bass and treble audio range), but benefit is you can have more frequency channels on the same range.
On wide channel bandwidth such demand on commercial radio broadcasting 87,5-108 MHz where people are listening the music and demanding high quality sound reproduction, you need to modulate whole audio spectrum from 20Hz-20kHz the basses, midrange, treble, then stereo subcarriers, pilot, left an right channel, you need wide bandwidth such 200kHz, that means 100kHz down and 100kHz up from main frequency carrier to compress whole information.
The television channels take even wider bandwidth 8 or 9MHz, that means 4,5MHz down and 4,5MHz up to modulate sound and picture on frequency carrier. Previous when was TV analog modulation you could on one channel modulate only one TV station. Sound was FM and picture was AM modulated, today when is digital broadcasting you can modulate on one frequency TV channel up to 10 different TV programs which package of different TV programs on one frequency is called multiplexer.
Thank you
You are welcome!
Thanks Sunny. Very vivid. However, I'm a bit curious, if FM is immune to static, then why using AM sometimes? When will AM be used? And why？
AM can travel over a longer distance.
Thanks sir! Very informative videos. I am from Pakistan
You are welcome, Altaf. I am from China, originally.
2:44 when we talk about data transmission, when we mean that we have a high bandwidth, then we have a high frequency range and thus the data can be transmitted over a longer distance, as far as I know. But here it says that AM frequency range is lower and that's why it can cover larger areas, and that would contradict what I said before. What am I missing? >.
higher freq = higher bandwidth but lower area coverage.it also used in 5g that they have to built many nanocell to gain more bandwidth
there's no such thing as "AM frequency". What you are missing is that on high-frequency bands there simply is more space ("bandwidth"). On mediumwave and longwave, stations are just 9 or 10 KHz apart. On shortwave they can be 5 KHz apart. On the FM-band (aka "3-meterband"), that is 87.5-108.5 MHz, they are at least 100 KHz apart. Also, the higher the frequency, the more information you can modulate
@@farenzu4578 "higher freq = lower area coverage". Not necessarily. Most high frequencies all have a comparable area with a radius of a few dozen kilometers. 5G needs more stations than other frequencies because it uses a frequency of 600+ MHz that gets absorbed by oxigen - just like visible light gets absorbed by fog
I still listen to am radio mostly for live sporting events.
It depends on your location. some times AM is very clear and stable.
Why does the lower frequency range of an AM cover a larger area?
Because lower frequency means larger wavelength and hence larger area.
Groundwave/Skywave propagation.
Wrong question. Low frequencies (longwave, mediumwave, shortwave) get reflected by layers high up, whereas high frequencies like UHF go (almost) straight into space. These things are notr dependent on modulation-type
you are my savior
Thank you for watching!
sir, why FM affected by physical barrier
The best
Thank you!
2:51 most of News radios are AM 原来是这样。我在aged care工作时，喜欢听新闻的老人。频道里一直都是新闻。原来是这样
Would you like AM or FMM
I prefer FM locally.
how can it be different if the carrier signal is the same?
Can someone please explain it to me
Great, but 1.25 speed is the savior.
i use 1.5
sir please explain phase modulation as well
phase modulation produces by FM mostly same concept.
Simulate some circuits! Arrive at: androidcircuitsolver/app.html
Thanks again, God bless you
Effff emmmm... No static at all (no static at all) 🎶🎵
is to say thanks enough for you mr bitght man ?
Thank you for your nice comments!
i just thought am was weather and emergency stuff and fm was music LOL
hi
Hi
Steeley Dan ..............................
are you sure ur facts are right?