Is AM radio dying?

why does locking the freqency but changing the amplitude make a shitter sound?

Analog audio is dead.

Amplitude is more easily distorted than the frequency.

sometimes i hear planes talking through AM radios, but that's it.

>tfw still have no clue how FM works
Like, what are you even picking up if the frequency is constantly changing?

Each station has a specific center frequency and maximum variance from that so as not to overlap with another station. It isn't complicated.

my city have 30 AM stations, it still alive

Your thinking of FM radio.

I want (you) to buy a shortwave radio

Attached: 1529796291602_0.png (315x552, 120K)

This is only due to convention of using AM at lower frequencies which is a result of lower frequencies being historically easy to produce and AM being easy to produce

This statement is sorta confusing can you clarify?

Not him, but lower frequencies travel farther than higher frequencies. Lower frequencies can be heard for thousands of miles because they bounce between the atmospheric layers (D, E, etc.) and the ocean/ground.

Lower bandwidth signals also propagate farther and more efficiently. AM also has a considerably lower bandwidth than FM. Sideband (USB, LSB) has an even lower bandwidth consumption still and replaced AM as the de facto modulation type used by hams many years ago.

Not anymore than any other terrestrial radio. AM is still the fastest way without using a computer/phone to get fast, up to date news.

Remember sitting next to the radio listening to the local station at 6am to see if you were getting a snow day? Do you really want your kids to be deprived of that simple joy because you looked it up online or got a tweet (or email) from the school?

>but I always have my phone
you shouldn't use your phone while driving
>but I need to know NOW
you can probably wait 10 minutes. You're going to waste those 10 minutes before or after you find out whatever it was you were looking for dicking around online.

traffic on the 3's, weather on the 10's, breaking news when it happens.

Frequency allocation is fucking ancient and the reason AM is used at low frequencies is because that's the only thing that was technologically possible. FM became practical around the same time VHF became practical so FM transmission was allocated to the higher frequency, the only thing preventing long range low frequency FM transmission is the FCC.

Thanks! I actually knew all that except the bit about Sideband. I was just a little confused about what exactly they meant.

AM and FM also have a different modulation / demodulation process correct? AM being amplified 'signal' riding on a long wave (Low band) and FM being frequency mod'ed on a short wave (High Band)?

Right..

Isn't most cellular carriers (ATT, etc) like 1700 Ghz to 2160 Ghz ?

Lower frequency = higher wavelength

Of course they have different modulation/demod processes, what do you think AM and FM stand for?

I live decently close to the border and so I end up receiving a lot of American origin and Mexican frequencies so most of AM is taken up. FM still has a few clear frequencies that aren't taken up though.

Sorry my terminology is off.. Which is kinda dumb based on the fact that I have experience working with DAS systems as well as TVRO and VSAT

AM is literally shit
- frequency spectrum is twice as large as needed
- half the power is wasted in the carrier frequency
FM and SSB (which is popular with HAM) are way better for analog

(((They))) want it to be because the internet is already 1984.
Norway starts the fire:
money.cnn.com/2017/01/06/technology/norway-fm-radio-shut/index.html

>AM is shit
>What is QAM

BBC Radio 5 Live and Talk sport are on medium wave but apart from that it's ded in the UK. You also get blacks and asians listening to pirate radio stations on me to listen to their own shite.
Radio 4 is on longer but apart from that the band is dead, I doubt anyone listens to longwave any more.

So is it possible to send small packets of data over AM?

all radio is dying (and that's a good thing)

Attached: 1528758277020.gif (210x161, 1.74M)

AM = Amplitude Modulation - the amplitude (voltage/current, depending on phase) is modulated.

FM (or Phase modulation) - the frequency of the carrier is modulated and shifts up and down within a specified range.

Up through 3G, it's 800/900/1800/1900/2100 worldwide.

LTE has around 30 bands, from around 700MHz through above 3GHz, depending on region.

More like 700MHz to 3.8GHz.
spectrummonitoring.com/frequencies/

>spectrummonitoring.com/frequencies/
Awesome! Thanks for this link.

So where is 5G suppose exist on the spectrum and is there a roof?

For analog stuff AM is garbage, which is what this thread is about
QAM is great but not very power efficient.

Two dimensions to check here:
Modulation: AM is just inferior in terms of quality and additional services, when compared to FM, DAB, SiriusXM, etc.
Frequency bands: LW/SW radio isn't practical: there's too much interference in big cities (blame chink/kimchi shit), and you need big aerials to get a good reception.
US specific: Satellite radio blew the last frontier where AM outperformed other techs: extended range.

600MHz in the US, 700MHz elsewhere, 3.4-3.8GHz seems to get universal traction.
26 ~28GHz depending on the country.

BTW, the recent years technological evolution with antennas (especially beamforming) enables 3.4-3.8GHz to have similar coverage/performance as 1.8GHz used to have on older generations.

mmWave (>6GHz) will be used for ultra high density cells (like on a bus stop, for example), and for self-backhauling (some base stations won't need dedicated microwave links to get hooked back to the backbone).

You now remember the existence of stereo AM

Where do I learn about RF? This shit is black magic to me. I played around with an RTL-SDR but didn't learn shit, just ran a bunch of premade software. I wanted to implement my own demodulator in some programming language but all the resources are graduate level electrical engineering textbooks/lectures.

>BTW, the recent years technological evolution with antennas (especially beamforming) enables 3.4-3.8GHz to have similar coverage/performance as 1.8GHz used to have on older generations.

>mmWave (>6GHz) will be used for ultra high density cells (like on a bus stop, for example), and for self-backhauling (some base stations won't need dedicated microwave links to get hooked back to the backbone)

This shit's super cool. I wish I had more hands on experience back when I was working on RF systems.
I did get to take apart and rebuild a DAMM Tetra Base Station a couple years ago but really didn't fully understand how it worked minus the idea of it demoding RF and modding it into a digital signal for hand radios.

It would be possible, however, it wouldn't be an efficient way to do so.

Most efficient modulations to transmit data are OFDM and/or FBMC coupled with error correction. It just deals in a better way with multipath interferences, plus you have a better spectral efficiency.

FBMC is more complex (in terms of signal processing) than OFDM, but it mitigates the spurious emissions. In best cases, you don't even need RF filters (check cognitive radio).

Attached: ofdm-vs-fbmc.png (870x575, 93K)

Thanks for all the info btw

>still the fastest way
>you can probably wait 10 minutes
user debunks himself

long wave is where it is at, bois

the only thing on AM radio is either 24 hour sports which borders on enthusiastic lunacy or neoconservative right-wingnut blatherings, so yeah, AM radio is dead

/hamg/ when

The thing is, signal processing and information theory heavily relies on advanced maths.

You can learn and understand the concepts and properties of different functions/algorithms/modulations without an advanced level in mathematics, however, depending on the level you expect to reach, implementation is another story (it's a wide and rich field for research).

Where do I start to get a working knowledge of the signal processing blocks in GNU Radio?

>tfw none of you know about DRM. DRM is going to bring back AM and SW broadcasting, why wouldn't you want to listen to your favorite stations in crisp, high quality 8 kbps digital audio?

Where my AM bros at

Attached: lamp_clock.png (542x540, 620K)

The spectrum between 30mhz and 50mhz should be released for public use on a personal telecom network.Imagine a world, a world where you buy a base station and can communicate with long range, with privacy and anonymity with your mother, sister, father be having to pay nothing and submit to a telecom oligopoly. Where each one is a small AT&T.

I'd suggest that link for general knowledge with signal processing: bores.com/courses/intro/index.htm

For GNU/Radio there are a bunch of tutorials online. (I've no idea of a specific one to recommend).

30~50MHz would require big aerials to be efficient (λ/4 being between 2.5 and 1.5 meter).

Going on air on a dedicated frequency doesn't provide privacy, as anyone can listen to the channel. Especially in a world where you can get an SDR receiver for less than 30 bucks.

And we're not talking of long distance communications (coast to coast, cross continental...)

Because ‘locking the frequency’ means making the modulation linear, so noise is completely additive on AM, meaning you’ll hear any noise if it exists unless it’s completely overpowered by the transmission. Modern AM tuners (especially in cars) have pretty aggressive filtering to remove noise at the high end but that also takes out a lot of the high tones of the signal. Meanwhile FM will almost completely reject noise below a certain SNR.

It's interesting to note that my local airport staff use AM modulation on higher frequencies, typically ~400 MHz according to the local repeater page. I can't pick it up with the equipment I have, so I guess it's true. Perhaps they chose it to prevent eavesdropping?

actually meant for

>chose it to prevent eavesdropping
No. AM at higher frequencies is standard in aviation because a third party can hear when two people are trying to transmit at the same time. Using FM is avoided because the FM capture effect means it’s quite possible for someone to transmit a message and for the intended recipient to neither receive it nor even know that they were trying to transmit (so they can’t ask for a repeat etc.)

how do i start pirate radio and how not get van'd by FCC

Broadcast in an unlicensed band below the transmission power and duration limits.

AM radio is 99% conservative talk radio. Kill it with fire

Transmit morse code by 50kW spark gap transmitter and shoot any FCC niggers

Most of northern Europe wants to kill FM, Norway already did it and Sweden will soon follow suit. It will be replaced with DAB+ which is a digital radio standard. The difference in practice is that if you're going through a short tunnel or valley or something then FM will give you a signal that's distorted and DAB is either clear or it just cuts out.

Anyway, this is a decision that really annoys me. FM was everywhere. Hell, most people still have a bunch of things capable of picking up FM. A few old people who still use radio (people 65+) bought those DAB radios. Most just stopped listening to radio. Perhaps I'd still listen to the radio once in a while since my phone, stereo, alarm clock and so on has a FM tuner. No way I'm paying a ton of money for a new device just for radio, though.

Wtf reviewcuck looks like that?

Podcasts have replaced talk radio for most people.

>No way I'm paying a ton of money for a new device just for radio, though.
You can use a SDR.

That sucks, fm is fine and there's no need to get rid of something standard which at this pint people dont give a shit about

the military uses USB for long range comms, I've sent text messages from japan to korea via HF radio.

youtube.com/watch?v=jCN6uAz9OfU

>lmao lets just fill up the EM spectrum with any old shit lol
kys

>let's just replace a long time standard supported by most technology in favor of higher quality when most people don't give enough shit to warrant the infrastructure change and out date all technology.

AM is dead and FM is dying

engineeringradio.us has some good posts about the decades of retarded bullshit from the FCC and station owners, and how it's killing AM in the US.

>start car
>turn off noise

Well, the changing frequency of course.

When radio became common place back then they had similar arguements regarding being deprived of joy because 'muh don't like change'. You are no different to them.

>what is WiFi phone/car connectivity.
Technically you can use your phone while driving.

it's a boomer Jow Forums meme that i'd fall

I was driving through central Oregon one evening and accidentally my radio and ended up on KOMO from Seattle. Sounded good too, really gave me an appreciation for AM.

>have old ghetto baster i use as an amp since you can remove the speakers from it
>AM always works while FM only works on clear days
>only thing on is boomers talking about zoomers or old classic radio stations
mfw

Attached: 1521563096283.jpg (354x286, 36K)

Holy shit, is this thread live? Just came to Jow Forums specifically to test the 0.01% chance it might have a ham radio thread.

What kind of ham radio possibilities might there be for someone living in an apartment complex with a concrete roof (no access to roof)? I have two empty rooms with windows facing east i could build some monster antenna in to compensate possibly? On the west side I have a terrace but it also has the concrete room, with some overhang.

My goal is just to listen to all the weird shit out there, not communicate.

I listen to Rush on AM.

He has a salary of 84million talking on AM radio. I doubt its dead.

youtu.be/KMIpZkraZxM?t=17

SDR + decent antenna
Cheap and flexible

Reporting

Attached: 42223586161_2c8ce5046c_k.jpg (1356x2048, 640K)

(no it's not)

Who /SWL/ here? The most patrician form of radio listening.

In my home town, the only station about 50km in each direction is a shitty AM channel. It sounds like such shit, and has worse range than the FM channels where I live now.

>sounds like shit
DIGITIAL
I
G
I
T
A
L

AM 700
Cincinnati WLW
America's Truckin' Network!

I can hear stations from India and China on a tiny scanner with a whip antenna.Sound quality is very good.

Why would anyone play radio in AM hours?

There is nothing to hear. Just endless Christian preachers.

Jow Forums is no place for this shit. got to make room for shopping guides and inane bickering

I work for a very large radio company. I can assure you that it is dying but nowhere close to dead. It's also a hassle to deal with from a technical standpoint so it would benefit us all if it died and everyone moved to digital.

it died like 50 years ago kek

But AM is supposed to be lower frequencies, that's why it has range.
The higher the frequency, the less range it has.