AM and FM Radio As Fast As Possible

AM & FM radio have been around since way before the digital age. How can radios decode AM & FM signals only using analog technology?
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[@asherb5134]

1:43 What's so cool about this, is that when I play my electrical guitar with headphones near my room windows. I pick up a radio station . at first it was scary I thought I hear voices

[@josephlouwerse2105]

wow thats weird!

[@plateshutoverlock]

It's called bleedthrough and it's very common with analog devices especially ones that are poorly shielded. They act like a rather poor radio reciever. I've had a few tape decks that doubled as low volume single station radio recievers.

[@RaidianaS]

@@plateshutoverlock I use a dongle with my iPad cause the case is too small for an aux cord, but dongles are fragile and sometimes I can hear the radio in my audio

[@vwestlife]

FYI: Analog signals aren't "decoded". They are *demodulated*.

[@ArnabAnimeshDas]

+vwestlife Linus uses codecs instead of modems xD

[@GrandadYT]

I wasn't expecting you here

[@nyandyn]

FYI: I got brain cancer from all this misinformation.

[@bhargavsaikia403]

VWestlife Can't we say modulation is a kind a coding ( without being technically accurate).

[@JimBob1937]

To add, digital signals aren't decoded either, they're also demodulated. Digital information is encoded in some form (or sometimes left as is), then modulated for broadcast, then demodulated, and lastly decoded. The encoding can give the data signal more favorable properties for the modulation that is to follow.

[@alexriley9002]

AM follows the curvature of the earth , well that’s a slap of reality to the flat earthers

[@daviduntalan]

wrong! what made you think of radio tower as high as tower buildings if it relies on the thought of your curvature earth?

[@tempeleng]

@@daviduntalan huh? hello flat earther. please explain how a spherical earth doesn't need high radio towers.

[@daviduntalan]

@@tempeleng oh i'm sorry i'm totally wrong, we need high radio tower even in your thought of spherical earth but i still believe that the earth is flat and the Sun is small than Earth and it's illuminating locally.

[@sampadagurung1]

@@daviduntalan The world has gone to shits. There too many Flat Earthers, Anti- vaxxers and "enlightened' conspiracy theorists claiming the Governnment is trying to control us through Covid.

[@Dirty_Dan02]

The earth is flat

[@abysspegasusgaming]

Put into consideration on how during WWII when 700 AM WLW (Cincinnati, Ohio) was broadcasting on an outstanding 500 KW of power, at which the entire world could hear the local news as well as keep the troops updated on the wartime news to the point that Hitler himself called the station a nuisance. Fortunately for anyone who would care enough, there's a video on here where a guy walks around the station and shows the massive retired all-tube transmitter, water cooling system, transmission antenna, and power transformers for the old 500 KW setup.

[@cwb7143]

Link?

[@donlove3741]

When you hear clear channel in their ads.. More wattage for your cottage! KGO WGN were also clear channels. They overpowered anyone on their channel. Today 700 WLW is clear channel after dark. 50Kwatts.. Located in Mason Ohio. Just up the road used to be the Voice of America transmitter array. Until they shutdown landline phones,tape recorders, phonographs would pick up VOA as background noise..

[@Schattengewaechs99]

1:00 The sound wave is not added to the carrier wave, it gets *modulated* with the carrier wave. By adding it you would emit your sound wave throughout the entire spectrum, causing heavy interference with every other radio station broadcasting.

[@oldolfmann8927]

I have watched a dozen videos of people explaining modulation... AM and FM, and no one seems to get it right. I was just bored surfing the web is how I ended up watching them. I understand how it works, and apparently you do also. Why don't these youtube experts? What frustrates me is the comments like "Wow I finally understand" So sad.

[@SamboHaxor]

Would you like AMMMMMM or FMMMM?!

[@dusliangames]

In the Netherlands we have DAB+ radio

[@boltgolt]

It uses the FM band though

[@pachipulususandeep5471]

FMMMMMMMMM

[@nyandyn]

Nope, DAB is broadcast on band III. That's around 200 MHz, not 100 where commercial WFM stations are.

[@doomedpepper8109]

Lol the Suite Life reference?

[@GeekTherapyRadio]

Gaze upon me and know me, for I am among the rarest human beings on earth. I have a full-time job on AM radio. Full....time.....job...........on AM radio.

[@Nostalgicguy2242]

What's your station name?

[@TetFeMal]

Damn.

[@loganricherson]

@@Nostalgicguy2242 idk but his username might be it, at least for his show's name

[@blockcamp]

what frequency and what power

[@NarciisJr]

Queen AM?

[@seancondon5572]

HAM and Shortwave as fast as possible! VHF and UHF as fast as possible! NTSC and PAL as fast as possible!

[@boiii3productions945]

NTSC is US/CAN standard (60 Hz 120V) PAL is the European/Australian/Asian standard (50 Hz 230V)

[@fb5601]

@@boiii3productions945 The voltages don't matter, NTSC and PAL are Video+audio standards

[@TheHoaxHotel]

Hey man, look at me rockin' out, I'm on the radiooo!

[@valtteri247]

SYSTEM OF A DOWN!

[@synanthrope]

Hey man, look at me rockin' out, I'm on the videooooo!

[@theeverythingchannel5457]

@@synanthrope With Danny and Lisa

[@synanthrope]

@@theeverythingchannel5457 Thank you for replying to a 2 year old comment

[@milicamaksic4414]

@@theeverythingchannel5457 they take me away frooom

[@hkoizumi3134]

My dad taught me how to make an AM radio using simple things found around outside. It's good for emergency cases when all other high-tech communication goes AWOL.

[@felix-zp4ie]

please show me how

[@choule90]

Some people just ain't meant to learn certain things and I'm one of them 😂😂 none of this makes sense to me but if you wanna give me a list of materials id need to make a speaker i might be able to process that

[@choule90]

Some people just ain't meant to learn certain things and I'm one of them 😂😂 none of this makes sense to me but if you wanna give me a list of materials id need to make a speaker i might be able to process that

[@choule90]

Some people just ain't meant to learn certain things and I'm one of them 😂😂 none of this makes sense to me but if you wanna give me a list of materials id need to make a speaker i might be able to process that

[@choule90]

Some people just ain't meant to learn certain things and I'm one of them 😂😂 none of this makes sense to me but if you wanna give me a list of materials id need to make a speaker i might be able to process that

[@aoeu6092]

Nicely explained, Linus. Though your explanation on AM vs FM when it comes to skywaves vs ground waves is easily misunderstood. Using the ionosphere to reflect radiosignals is done at longer wavelengths/lower frequencies yes, but regardless of the modulation scheme.

[@thomaseriksson36]

I was here 5 years later just to check that someone had pointed this out! :)

[@jamesslick4790]

@@thomaseriksson36 TBF, the is focused on the commerical AM/FM broadcast bands. It IS possible to use FM on SW or (even MW) frequencies,That explaining that might be a bit "out in the weeds" for a "Quickie" video.

[@oldolfmann8927]

@@thomaseriksson36 HaHa.... so many errors in this video

[@Exodus227]

If you had posted this a few weeks ago, I would've passed my Physics exam! 😂😂

[@AviatorMage]

+Exodus227 another one down. RIP in pieces.

[@Exodus227]

+Aviator Mage Forever remember and carry on my legacy.

[@Pax.YouTube]

+Aviator Mage Never forget..

[@Pax.YouTube]

+Aviator Mage Never forget..

[@gretawilliams8799]

Fuck Off Now, Dropout

[@aohige]

Yes, Justin Bieber's "Greatest who put that shit in my script" is indeed an amazing album.

[@flysledder]

Wow I literally asked myself this question about the difference between AM and FM a day after this video was released.

[@battmarn]

"Death metal" - picture of Mick from Slipknot

[@DLBBALL]

Was wondering if anyone else noticed...

[@thrawl]

hahaha I love death metal... I hate slipknot

[@modifidious]

Lmao

[@djapster]

lol. 99.5 FM is actually my favorite radio station where I'm from.

[@CDNSpartan]

Mine is 88.1 FM

[@k.c.slawncare6046]

103.9

[@bjornsan]

+djapster Nothing here att 99.5 but at 99.2 ther's a local radiostation which is mostly some old religious guy speaking about Jesus. I prefer 98.4 which is a swedish station or 93.9 which is a danish station.

[@chrstfr6834]

99.7 here :D

[@residentweeb2654]

94.7 here

[@noblessus]

Great explanation, makes it look much simpler than what i thought it was. Please also do a dynamic vs basic disks as fast as possible!

[@k6usy]

You can transmit and AM or an FM signal on basically any frequency. Broadcast bands have been established that places commercial AM broadcast on lower frequencies (535kHz to 1700 kHz) and places commercial FM broadcast on a higher frequency band (87.5 Mhz to 108 Mhz). With the right equipment you could easily transmit an AM signal inside of the commercial FM broadcast band (87.5 Mhz to 108 Mhz). I have a transceiver at home that allows me to transmit AM at 144Mhz or FM at 28Mhz. AM and FM are modes, bands and frequencies are different.

[@xnamkcor]

Someone once told me that Radio was sound waves....I cried and laughed on the inside at the same time.

[@bassdrumflextime1253]

Lol

[@WAQWBrentwood]

Radio trivia note: The old (analog) NTSC television signal used both modulation types: AM carrying the video portion, FM carrying the audio!

[@ChristopherdeVilliers]

Wow I am very impressed by how good the complexities of radio modulation were described by using very basic analogies. The "transformer" used in FM may not be the right word (at all) but that can be forgiven. As an engineering student I say well done!!!

[@tratzum]

IF modulator? Discriminator? Oscillator? Radio tech is weird.

[@JimBob1937]

Trust me when I say that while this is a good high level overview... the actual math behind AM and FM can be a bit mind boggling. Learning digital modulation techniques now and to start we covered AM/FM. Trying to find the frequency spectrum of an FM signal of a certain data signal and carrier frequency is a pain in the butt. The practical solutions that we learned still only estimate it (carson's rule, bessel functions...etc). Additionally, one might be interested in knowing that FM itself is only a type of angle modulation, one can also instantaneously vary the phase of a carrier signal to represent data (PM), the result looking very similar to FM but tracking different data signal properties.

[@pclover]

AM and FM have nothing to do with wavelength... they are just modulation types. FM broadcast band is typically 88-108 Mhz while AM broadcast is 540 Khz to 1700 Khz in the US. This is often called Medium frequency band. Medium frequency can bounce off the ionosphere at night. FM broadcast is in the VHF band and is typically line of sight. There is cases where you can here it for long distances. Tropospheric ducting and bouncing off the ionosphere called e-skip. These effects however are very rare and uncommon.

[@Ben-fn2eb]

Question: If you modulate the frequency as in FM, you automatically modulate the wavelength, or am I mistaken? (I'm very knew to grasping this subject so your comment threw me off - 5 yrs later lol) Be well

[@oioi-dn4bu]

@@Ben-fn2eb yes because wavelength is directly proportional to frequency -> wavelength=[speed of light]/[frequency].

[@Ben-fn2eb]

@@oioi-dn4bu hey, gotcha.i wasn't thinkinhg with the speed of light being a constant factor, thank you!

[@pali1H]

I miss having FM in my android phone. My first one back in 2010 was a Droid X and had FM radio!

[@atotmix]

+Robert Tinsey sony xperia z5 still has it :P

[@megakiller999]

+Robert Tinsey Some can still use FM radio by using a Bluetooth headset as an antenna. I know my windows phone can.

[@alcidiow]

+Robert Tinsey still rocking my fm radio with my lg g4

[@stephensnell5707]

​@@alcidiowwell dump your lg phone as I bet the battery is so old I bet it doesn't even hold a charge long at all and remember you can only use wired headphones with a phones fm radio(wireless will not work with it,only wired will)

[@skaixx1864]

>death metal. >slipknot image

[@mathijs2100]

Came for this

[@SiktecDubstep]

+Brewskai I used the search function as soon as I heard that.. LOL

[@TylerSteven9]

+Brewskai >greentexting

[@skaixx1864]

+Steven Tyler lmao you think

[@slendermike3206]

+Brewskai exactly my thoughts

[@HamRadioCrashCourse]

Great video. Good job!

[@Kodo-Nashi]

Dude, Josh also watches LTT, we are basically friends now.

[@smt4090]

would you like *AM* or *_FMMMMMMMMMM_*

[@alexanderquilty5705]

Also, FM is actually a subcategory under something called Angle Modulation. Angle Modulation consists of Phase Modulation (PM) and Frequency Modulation (FM). This is because in application they are varying the angle in a cosine function. Thus the name: Angle Modulation. FM actually changes the frequency, but when you add an angle in the cosine function, we call that the phase modulation, and pretty much just shifts a signal left and right (hence the name Phase Modulation).

[@warrenpuckett4203]

It gets a bit more complicated with radar applications.

[@zahabahmedqureshi1303]

I can't believe the perfect timing of this. I have my physics exams and AM and FM are part of the syllabus. Thanks for this, Linus. :P

[@NizarElZarif]

+Zahab Ahmed Qureshi you probably need to study anyway :D. These information are pretty basic.

[@kdoe1305]

I think AM radio is adjusted by a ferrite rod going in and out of a stationary coil. It's not the coil changing its structure, although mathematically it is changing its inductance.

[@luketimothy]

+K Doe For tuning? I believe that the aerial is pretty close to a potentiometer, if not actually a potentiometer.

[@kdoe1305]

+luke timothy I remember analog tuners used both adjustable coils and capacitors. Newer digital tuners tend to use potentiometers, as it's just some voltage difference input to a chip that controls everything.

[@luketimothy]

What is a potentiometer if not an adjustable coil?

[@joelandjake]

Here in the Philippines, FM is for music, and AM is for news! XD

[@nellvincervantes3223]

Hehe. Tama (Correct).

[@KRAFTWERK2K6]

The benefits of radio are simple: The infrastructure already exists and receivers are absolutely available at any price range, from old to modern. Even a radio from the 50s and 60s can still be used. Receiving doesn't cost you anything and nobody can trace you back, unlike webradio streams. Plus radios usually run on low power and have a long breath.They can be powered by all sorts of energy. Some radios even run on a kinetic energy dynamo that is powered by a spring movement and don't require any batteries at all. You can even build your own custom radio the way you want with fairly cheap off the shelf components. All that matters is what type of style you prefer. And another benefit of analog radio is that even if the signal quality is weak, you can STILL hear the station through the noise. If the signal of a digital transmission is too weak you get nothing at all or just eardrum shredding glitchy noises. Analog radio is basically THE BEST medium (still) to reach the most people around the world.

[@getsomebud]

> death metal > shows Slipknot's Mick Thomson

[@kunstderfugue]

+Alex Ehler (THOUGHTSEIZE) i lol'd too

[@deadviny]

+Alex Ehler (THOUGHTSEIZE) how dare he

[@jacobmartincontreras]

he should have shown lord worm feeding his fans worms

[@berthold64]

>greentexting

[@MrJackojc90]

+AyyGin No, It's Nu Metal.

[@codyoftheinternet]

Another note (years later): at night there are actually less ions in our atmosphere. The reason AM goes further at night is less interference from the sun which, during the day, easily overpowers our AM emitters

[@TheFilledk]

Linux As Fast As Possible!

[@Grownupfun]

I'd rather do linus as fast as possible

[@TheFilledk]

+Hunter3901 narh man, Linux is more popular!

[@marioftw6182]

yes

[@Grownupfun]

TheFilledk no I would DO linus y'know what I mean?

[@MasterYoshidino]

Did not take long for someone to make this into innuendo.

[@kd1s]

Now from the perspective of someone who has an amateur extra license I'll tell you more about FM. It experiences one thing you missed called Tropospheric ducting allowing a 5 watt transmitter to reach 200-300 miles out. Has to do with what are called temperature inversions.

[@TheLordsDeciple]

kd1s I love tropo!

[@FrostByte_AC]

Thumbs up for the picture of Mick Thomson. That guy is like my Kobe.

[@VeganoGuy]

There are fewer free electrons at night. (The solar radiation frees electrons). Lower frequencies in the AM band are reflected a night because the free electrons that block the reflection re-join the atoms. However frequencies between the AM band and FM band are referred day and night.

[@nextlifeonearth]

If I put on the radio there's only 2 things I hear: pop music and commercials. I hate both with a passion.

[@KlodFather]

You must be really old and crabby... I'm old and I like pop music, techno, and dance. Even though Im too fat and uncoordinated to dance LOL Weebles Wobble but they dont fall down ha ha ha

[@Joseph-lp8of]

I hate both. I wish it’s more sorted out

[@jamespfitz]

Change the station, dipwad.

[@ethanwagner6418]

Bruh, I used to receive a noisy signal from a metal/alternative rock station, and then some jackass decided to overpower it with Christian pop.

[@thrawl]

I am right there with ya... pop music is a horrible horrible thing

[@leadwayvideoproductions7881]

Windows Registry As Fast as Possible

[@ashiqsultanmohamed9765]

yes, it would be great

[@cloroxbleach-si4jp]

+FlappySock xD you got that from Pyrocynical, right?

[@3lH4ck3rC0mf0r7]

+LeadwayVideoProductions This is good, though technical.

[@3lH4ck3rC0mf0r7]

***** Not really, but to modify or tweak it requires technical know-how.

[@3lH4ck3rC0mf0r7]

***** Well if you just mess around with system keys you will probably wreck your Windows...

[@ChompXephr]

"WOULD YOU LIKE AM OR FM", the first thing I thought of when I saw this video, now if you will excuse me, I need to fix my car, I think the prndl is broken.

[@Valkitsune]

Mr. Moseby op

[@shanehampson8704]

i thought the same thing

[@kiko1992]

One of the rare , easy to understnd explanation of AM FM ! tx

[@caribbeansimmer7894]

Sorry to break it to you but this videos has serious errors.

[@shanemacdonnacha4193]

I fixed an old radio for a friend but i could only get foreign stations. I remember a Chinese one and a Spanish one and if memory serves me right a Russian one too. This was from Ireland and the radio was in a place FM radio would have trouble picking up a local station, So if somebody can explain id appreciate it :)

[@Pyroja]

It's pretty amazing to pick up some of those far off AM stations at night. I remember driving through Nevada and picking up KCBS loooong before I got close to the border.

[@Treetop64]

Learned all of this years ago at Avionics School in the Coast Guard, and this guy does a very good job explaining things spot on and very succinctly. I'd like to see him explain, in an equally efficiently manner, the math behind finding the voltage drop on one resistor on a circuit board. That would be interesting. :)

[@warrenpuckett4203]

I went to EW school. I know NOthing, nothing Like SGT Shultz kzbin.info/www/bejne/fpPPgaiZrLNgo5I

[@kieferonline]

Wow, thanks for covering this topic! Some relevant tech here! Learning about radio and sounds, for me, was the way I started learning about electronics. Wireless sounds are fun.

[@James.Schiliro]

WELL, I have to watch this for school... i love linus

[@withlove1887]

3:35 That wave's AM, so that's correct 3:40 That wave is still AM dude (Its not FM) lol

[@Roskellan]

The distance a signal travels (given all other things are equal) is related to its frequency - a FM signal will travel as far as an AM one at the same frequency.

[@wumbosaurus9121]

Why don't we just reLAAx, we'll turn on the raADIOoo? Would you like AM, or *FFFFMMMMMMMMMMM?*

[@DanTheMan1985ful]

That's what this generation of the Digital age needs to do. They need to learn how to Appreciate what we DO have just in case if something DOES happen to the Internet that they depend on SO much. Don't go discarding OLD technology just because we live in the Digital Age. That Old Technology COULD save your life one day. Put it in another way, our way of life may revolve around Modern Technology but the Forces of Nature out there doesn't such as the Storms that we see from Mid Spring to Mid Winter Tornadoes, Hurricanes, Earthquakes, Floods and Blizzards. The Cloud-to-Ground Lightning, Gusty (+60 mph) Winds, Moving Ground, The Rain and the Ice that falls from the sky can knock out or Potentially destroy the electricity on the Utility poles that y'all depend on for your Wi-Fi needs. Can't Run Wi-Fi and get the Information you need without electricity. They can throw you into that situation. Where you're left with an old battery-operated AM/FM radio as your only resource for information. Now your Smartphone may have a chance of getting information without Wi-Fi through the Cell Phone Tower that is if you don't mind using data for it or if the Tower itself is not in the path of that particular storm where it can be destroyed. If your Smartphone fails on you during that situation your gonna need that Old Radio to let you Know of what's going on.

[@JYMBO]

Wish you included DAB radio in this video :(

[@SigurdKristvik]

+BLAQSONiC well it's more expencive, complicated and not world wide adopted. My country started getting DAB in 2011. but people still use FM and AM. So my goverment is shutting down FM and AM to free up these frequenzies in 2018? or something like that.

[@SigurdKristvik]

BTW.. I live in Norway.

[@SailorToBoat]

+BLAQSONiC its the same as fm but instead of using a audio signal to modulate the frequncy it uses digital signal so on or off where high change in frequncy is on low change is off.

[@nicolaibratsberg9967]

True. Norway is shutting down FM this year...

[@stephensnell5707]

​@@SigurdKristvikyou mean frequencies and expensive

[@haavasny]

In my Norway we don't have AM stations anymore and the FM stations is going to go down in 2017, so we are switching to something called DAB and DAB+. Is that happening to anyone Else?

[@nellvincervantes3223]

Nope. AM and FM are still being used here in our country. And I have no idea about DAB and DAB+.

[@UnrealOG137]

How LCD screens are made as fast as possible

[@GonthorianDX]

+SecretPotatoChip Today on How Its Made: LCD Screens

[@AnsliKrow]

+GonthorianDX I was gonna say this isn't how it's made haha

[@MoisesCaster]

SecretPotatoChip I would like to known too hahahaha

[@karlkarl93]

+SecretPotatoChip Check out engineerguy on youtube, he made a good video about screens.

[@billete37]

First we need to get lots of water.....oh lcd not lsd sorry dont mind meee

[@rnklv8281]

The way I'm interpreting his video is that when you tune your radio receiver to a certain station, your tuning to the carrier wave frequency. The carrier wave is just that , a "carrier". The stuff you want to listen to (also a analog signal) is superimposed with the carrier wave, then off they go into the wild blue yonder. Your radio receiver's antenna will pick up the signal, as you are tuned to the carrier frequency (if I' m interpreting his video correctly) .

[@Firetech2004]

One thing I found weird with fms is if you’re listening to 99.5 fm (for example), and you switch to 99.4 or 99.6 you can still hear the same station as 99.5 although you can hear some static. I live in India and here we have more fm stations compared to am. I listened to both fm and am and I find that in am volume goes up and down and in fm I can hear static sometimes.

[@ILikeWhatILike69]

Thats why the frequencies tend to be separated more. Like the radio would jump from 97.0 to 98.0. That gap reduces interference. Using decimals makes interference have a higher chance.

[@jeffdwyer6105]

Pretty good but you strayed a bit when describing the distance part (at the end) Emphasis was needed to explain that its not the MODE (ie AM-FM) which increases distance but the commonly used frequencies . I would have used the term "AM Broadcast band" and FM Broadcast band . Signal to noise ratio would explain range issues also but that wouldn't be making it simple .

[@Cat-ir8cy]

I thought AM was morning radio and FM was afternoon radio .-.

[@fretic777]

me too

[@boiii3productions945]

actually it is not morning/afternoon it is amplitude/frequency modulation

[@Nostalgicguy2242]

@@boiii3productions945 actually he's right about "AM" being "morning radio", the human ear isn't meant to perceive the loud, blaring, stereo sound from FM signals anytime before noon.. The kids who wake up to FM radio go deaf in their 40s....

[@richrdmgol7965]

Yea man me to

[@RR-ho3td]

@@boiii3productions945 He's right about morning radio being AM. Even the clock agrees! If you get what I mean. XD

[@FrostyDog9186]

Slight correction, whether a signal propagates via the ionosphere has nothing to do with the signal's modulation, but entirely to do with the frequency. Signals below 30MHz tend to propagate via the ionosphere much more readily than signals above 30MHz. Since the AM broadcast band is from roughly 0.5MHz to 1.6MHz, and the FM broadcast band is 87.5MHz to 108MHz, the AM band bounces off the ionosphere much more readily. Amateur radio operators use FM on the upper part of the 10m band at about 29MHz, and it skips quite well.

[@JRob1125]

I find analog technology, although technically inferior, way more fascinating than digital technology. It seems so much more difficult to get right that the fact that it can end up sounding or looking as good as digital is mind blowing.

[@rty1955]

Analog technology can be improved not so with digital. With digital there is a finite standard (1's and 0's) in order to change any quality a new "standard" must be developed. With analog things just get better with better components.

[@stephensnell5707]

​@@rty1955however,more interference will always occur with Analog devices which is why Analog devices got phased out in favour of more reliable and higher quality digital devices

[@rty1955]

@@stephensnell5707 as analog devices get better, LESS interference or noise will happen, but in a digital world, everything is finite and requires a new "standard" to be compatible. You can improve analogy, but you cant improve digital

[@thechaoscraftcamtcc3770]

This seriously helped me figure out how radios work and how the Emergency Alert System (and the Emergency Broadcast System before it, and the CONELRAD/CONtainment of ELectromagnetic RADiation system before it) works and how you actually hear the annoying tones that tell you to 'Listen up, bonehead, because somethin' bad's going down soon or already is.' Thank you, Linus, for this explanation and your later one on the EAS, despite my knowledge of the latter.

[@thegoldeneagleeye9621]

Whenever I turn on AM radio it feels like there is gonna be an announcer saying 3 nuclear bombs has detonated in 3 major cities

[@zacharyferreira3730]

Thanks, for the lesson, you explained better than most.

[@stephensnell5707]

You dickhead,it is nothing like that It is only and explanation Video

[@scottpeterson7500]

Radio, the original streaming service 😎🍹

[@morgard211]

Very useful video but keep in mind that both, the AM and the FM are analog driven and as mentioned in the comments - the right word is rather demodulated than decoded. :)

[@WalnutSpice]

FM Radio, why is it popular? Free, sounds great, local

[@jjwarner9419]

+Walnut Spice Why are you everywhere?

[@WalnutSpice]

JJ Warner I'm everywhere all the time

[@jjwarner9419]

Walnut Spice So you're omnipresent?

[@Nostalgicguy2242]

Walnut Spice what are your favourite AM stations?? Name at least six of them....

[@spcyakima1077]

Yeah pretty much. Listening to radio is free, but you have to pay for the radio. :^)

[@FeTiProductions]

wow thats sweet. My father use to tell me he could hear radio stations from Florida back in the 60s (all the way from northern Jamaica), didnt know AM radio had that property

[@KaushikHarith]

+linustechtips IT IS NOT as simple as a couple of wires!!!! Tuner circuits are beautiful LCR circuits. When you turn a knob, you rotate plates which change the common area between parallel plates, thus changing the capacitance(C). This in-turn changes the resonant frequency of the circuit(because resonant frequency omega=1/root(LC).

[@vwestlife]

+Kaushik Harith It is also possible to make an AM radio using only a variable coil, instead of a fixed coil and variable capacitor. In fact, most older car radios used variable coils, known as "slug tuning".

[@KaushikHarith]

vwestlife Interesting! How would one change the no of turns of the coil/length of coil/Area of cross section? Those are the factors that magnetic field depends on and hence Inductance(because L is flux per unit induced current.). I can't picture any easy or efficient way of doing so. The only easy way would be to change the permiability, but that would limit you to using two frequencies.

[@vwestlife]

Kaushik Harith The physical coil of wire stays the same. To tune it, you slide one coil in and out of another coil, or slide a metal slug in and out of the coil (hence the name "slug tuning").

[@KaushikHarith]

vwestlife That is what I thought. But how would we get a continuous distribution of resonant frequencies?

[@afterliife]

+Kaushik Harith google it buddy.

[@pixelum2023]

It's interesting to know that FM radio was invented precisely to solve the static issue with AM. But the company owner was NOT happy at all. What he wanted was better AM radio, not a completely new radio system. That's why it took decades for FM radio to get onto the market. Nowadays, AM is basically dead and it's frequencies are being reassigned to other services like cellular phone networks and such.

[@skymanmusic8570]

Remember: sun up frequency up, sun down frequency down.

[@shirobonjp5185]

Misleading explanation of AM. It's a common misunderstanding, but AM doesn't tune to a single frequency. It can't be that way, since a single frequency alone carries no information. When you modulate the carrier, you introduce the frequency components from the modulator which are in the resultant AM signal. These are known as the sidebands, which are mirrored around the carrier. When you're tuning to an AM channel's frequency, you're tuning into the entire band allotted to each channel. Standard AM channels have a bandwidth of 10kHz, which is good enough for voice. This is why radio channels are never adjacent, you need the entire bandwidth for the transmission as well as a buffer area between channels to minimize interference. It's impossible in the real world to tune to a single frequency, since no perfect filters exist. That's also what the resonance circuitry is acting as, a filter. If you were able to just tune in to the frequency of the carrier, that's all you would receive, the carrier. Which carries no information by itself. All the information is in the sideband.

[@StarGateSG7]

Hmmmm.... Technically, you could use TIME-based spacing of pulses at a SINGLE FREQUENCY that can contain information IF it is broken up into pre-determined time slices representing numeric values to create digital broadcasting-based bits and bytes. That is kind of like using Morse Code but happening with the time-based spacing allowed within the Megahertz of FM and Kilohertz frequencies of AM radio. V

[@Uncleharkinian]

“A.m. is fine for talk radio” tell that to my boss lol

[@owenchuarbx]

Thanks for the recap, needed this for an exam

[@sterlingtardie]

What would it take to receive permission to show this video to communications students in a community college classroom (as a basic introduction to transmitters and receivers)?

[@shipshrekt2156]

sterlingtardie Email them.

[@richmarks8578]

I love to dx AM radio at night. The furthest station I've picked up was AM 870, WWL out of New Orleans, which traveled almost 1900 miles. AM 1040 WHO is a common station here too, which is roughly 1500 miles away. DXing is so fun. Its the thrill of finding that long distant radio station, way, way out their. You need a good AM radio though, with a good AM antenna. I never have tried, but the "graveyard" frequency's are a jumbled mess, but there are people who try ( and successfully catch ) distant radio stations in the rumbling audio.

[@Embattled5211]

Windows Restore Points as fast as possible?

[@repeatrepeatrepeat]

Bullshit

[@tysonkillion4840]

+blueman24 youre right

[@LANESxNOWONLYx]

Due to the propagation of FM waves, distance is a factor. Being that FM waves propagate horizontally & the Earth is spherical, the radio receiver will, based on distance, drop below the line of horizon & beneath the propagated FM wave. The reason car radios begin to loose an FM signal as the vehicle travels farther away from the FM transmitter, is for this very reason. FM waves propagate horizontally in a complete circular pattern from the transmitter's focal point, as seen from a top view.

[@chasetherightenergy]

Do VHS as fast as possible

[@JoshuaSingh94]

Nice video! I'm the Chief Engineer/Operator for my college's FM radio station and this was a nice overview of the technology.

[@andreassonne8004]

I would listen to radio, but I don't have a car yet...

[@blockcamp]

i operate a pirate FM station at 108mhz and 35w is pretty good for a pirate station. Considering the signal travels like 100km it's pretty good.

[@borrellipatrick]

my phone's loaded with music streaming apps but a lot of the time...I'm just listening to a local fm radio station on the next radio app that unlocks the fm chip in the phone :I

[@dodovomitory3496]

what is your phone?

[@fa.h.]

+majed .salame My phone, GTC m7, have built in FM radio, just need to use headphones

[@borrellipatrick]

+majed .salame I'm currently using a Samsung Galaxy j3 2016. I'm also on Virgin Mobile (prepaid Sprint) I know most android phones outside the US have the fm tuner usable but it's locked away over here. Sprint lets their phones use it but with an app called Next Radio. Most there for sone added ad revenue though o_o

[@antonio1681]

@@borrellipatrick oh yeah

[@ericcartmann]

Thanks for the flashbacks to my signals processing course linus. I really needed a good dose of not knowing what is going on.

[@WhyWePlayTruckSims]

what about DAB?

[@sanicmaniac]

Well reverse that word for your answer Edit: oh wait nevermind this comment is actually from 2016 or 2017

[@Rowsdow3r]

I had to learn all of this in college. I found it to be super interesting while my classmates were bored to tears to have to learn about it.

[@kirtthelander6912]

why are radio station frequencies end in an odd number? its always 98.9 or 104.5 but never 100.6 or 99.8?

[@kirtthelander6912]

I know that there is a .2 difference in the frequency to keep stations from bleeding together but why odd numbers?

[@DarthBagel]

There a radio station in my area called power 98 but they are 97.9 on the radio channel

[@HackerQuacker]

it's because odd numbered frequencies have better range that even numbered frequencies for some reason.

[@kirtthelander6912]

+Suhkma Dheek yes. I understand now. thank you

[@vwestlife]

+Kirt Thelander FM stations in the same area need to be spaced apart in order to avoid interfereing with each other. In North America this is accomplished by allocating the FM channels only on the odd frequencies. In other parts of the world, they use both the odd and even frequencies, to allow more stations to fit on the band. (AM stations are also allocated on different frequencies in Europe and Asia, with 9 kHz spacing between channels, instead of the 10 kHz spacing used in North & South America.)

[@AutisticThinker]

@1:32: No, It doesn't "make your antenna resonate at the same frequency and ignore everything else in the air"; you even say so @ 1:45, you are describing a band-pass filter. The antenna gets all of frequencies that are a close match in length to the specific frequency they are designed to pick up (full wavelength) and can also pick-up resonate frequencies such as... 2x, one half, or one quarter wavelength. That's why there is no such thing as a "digital antenna" (they use the same frequencies as analog did).

[@rogerwilco2]

Hey kiddo, you're not old. Your first computer was a AthlonFX.

[@logaandm]

AM - Ancient modulation FM - Freaken magic FM is pretty special as it is at the heart of many types of digital signal transmissions. It really is magic.

[@boiii3productions945]

^Frequency Modulation

[@boiii3productions945]

@Command64 ok

[@xmichielx100]

DAB Radio As Fast As Possible!

[@snacksy7754]

i'm a bit disappointed that you did not mention DAB radio. because in Norway everyone MUST change to DAB radio by 2017 and all FM radio stations are being shut down. I know it uses satellites in space and stuff. Would love to know more about that

[@AnimilesYT]

well, too bad AM and FM radio will be gone within a few years. well, at least here in the Netherlands. (fun for those who do not have digital radio in their car)

[@AChannelFrom2006]

It's been a few years... is it gone yet?

[@JamesEllison69]

IDK bout FM, but with AM, yea.

[@thanhluan3800]

well how's it (AM) in 2022? anyone got an answer? cause i'm gonna get myself my first radio ever and there are some FM only radio that catch my eyes but i was worried about missing that AM wave which can bring me surprises some days. thank you :')

[@kaylaandjimbryant8258]

The tuner (L/C) resonates, not the antenna. VERY FEW people have the land and inclination to put up a resonant mediumwave antenna. I give you a grade of C on the propagation bit. Actually the number of free electrons decreases the moment the sun stops hitting them. The reason for nightime propagation on mediumwave frequencies is quite simply the fact that the D layer disappears when the sun goes down. The D layer absorbs the radio signals, but is only present on the sunlit side of the planet. 73 de KC5VDJ

[@joebob2311productions]

Short Wave Radio as fast as possible

[@waterlubber]

+joebob2311 It's a variation of AM that takes out the carrier wave and just uses the difference (sideband) It then bends around objects or bounces off the ionosphere, similar to a laser through dust.

[@CocoaNutCakery]

+joebob2311 My first thought as well.

[@vwestlife]

+waterlubber No, that's SSB (Single Side Band) you're referring to, not shortwave. Shortwave broadcasting uses Amplitude Modulation, just in a different frequency range and with higher transmitter power levels, allowing shortwave broadcasts to be easily heard thousands of miles away. More properly, what we refer to as "AM" is known as Mediumwave (MW). In the Eastern Hemisphere, the Longwave (LW) band is used for AM broadcasting as well.

[@waterlubber]

vwestlife Well, shortwave covers the HF band of the spectrum and a LOT of broadcasts there are SSB

[@vwestlife]

waterlubber A lot of amateur radio operators use SSB, but not a lot of shortwave broadcasts. The vast majority of shortwave broadcasters use AM; some use DRM (Digital Radio Mondiale) and only a handful use SSB.

[@fuckyouandthehorseyouroadi8264]

Amazing! that what's is in the atmoshere hears and sends back its response

[@stephensnell5707]

You mean Atmosphere

[@notsurejr4957]

Bassiclly Am and Fm to me is, Fm songs, Am static.

[@richrdmgol7965]

Its true all that I hear on the am is static

[@duprie37]

I remember we moved cities from Melbourne to Brisbane 2000km away when I was a kid and I managed to just pick up my favourite AM station in Melbourne - 3XY Hot Hits 1422AM - at night with a really really big antenna.

[@sourcethunderlight2723]

Battery Percentage As Fast As Possible

[@koltonhennessey]

cool vid i think i am one of few people that still kept an old radio in the house just fore the set and forget factor as well as the variety of musick and no track skipping or crashed cds to deal with

[@oops_player7328]

One time my radio pick up unknown language but there music was catchy. You're video explained a lot what happened to my radio. My radio never pick up unknown radio station again.

[@stephensnell5707]

You mean their It simply is not possible for no Radio to pick up other stations across the world(the Radio simply isn't made to do that) Any Radio will only pickup stations that the user lives in an no others but that

[@Brunoxid0]

Slipknot death metal? C'mon guys!

[@theroyaleplayer5462]

Merci beaucoup Professeur. Je trouve cette vidéo trés utile...