> The service area of Mini FM is very limited only in 100-500 meter radius.
Post-Covid, work from home, internet deliveries the trend is arguably things have to distribute to people now rather than people distribute to things.
FM radios have all but gone from modern cellphones and vanishingly few people are carrying around discrete ones. BT serves this physically local radio purpose now and is pretty much everyone has it on their person.
So it might have had a past but it doesn't seem to have a future.
For receiving FM radio a lot of them do, definitely most of the feature phones that have a 3.5mm audio jack (the audio cable doubles as the antenna).
Some phones released around the 2010s also had FM transmitters, for example the [Nokia N8](https://www.gsmarena.com/nokia_n8-3252.php). The use case for these was to be able to listen to the music you had in your phone via your car stereo, since AUX ports and BT sharing wasn't common back then.
My understanding is any Android phone with a Qualcomm LTE modem and a physical headphone jack can tap into FM radio. The headphones are used as the antenna.
As the other commenters said, my Moto G Power has one, and you use the earbud cord as the antenna. It's super useful when storms knock out communication towers in our area because I can still get the local weather and news over FM.
Tragically, this question illustrates how successful that Big Tech (Apple, Google, Facebook and the telcos etc.) has been in distorting the free-to-air broadcasting medium and redirecting listeners to its PAID services (Apple store etc.).
The fact that someone is actually unaware that essentially all mobile phones were capable of receiving FM Radio (the standard free-to-air FM broadcasts) until Big Tech nobbled them proves the point.
It's shocking this has happened and that government has dropped the regulatory ball. Traditional broadcasters are heavily regulated and have to pay substantial license fees yet the likes of Apple, Google etc. can do what they damn well like without impunity in the absence of any such regulation. (We only have to look at the damage to the social order these behemoth companies have caused in recent years to see that they have to be regulated).
That Big Tech has managed to essentially kill the FM service on phones to the extent that people aren't even aware of its existence shows that government has abrogated its regulatory responsibly. Moreover,
I find it hard to understand why FM broadcasters haven't kicked up a huge stink over the neutering of the FM service, after all, it's in their interest that their broadcasts can be received on mobile devices.
It's high time this is rectified, a 20% tax or surcharge on every phone without FM enabled would solve the problem instantly. Government could easily justify this on the grounds that FM is a viable emergency service—when the internet goes down, FM would provide an emergency backup information service—one that it's already performed for over three-quarters of a century.
>FM radios have all but gone from modern cellphones
Is this in the same parallel universe I keep reading about where all modern phones don't have headphone jacks? Because every smartphone I've ever owned has had both.
i have no idea what this is about, and the translation from (i assume) the japanese is awful.
small personal pirate radio stations are nothing new - my little brother ran one intermittently in the early 70s covering quite a bit of lincoln, uk. as this was broadcasting from very close to the then lincoln police hq, my dad eventually shut it down, with prejudice.
Funnily enough now it would be quite easier to make a hidden one. Slap a GSM modem on one and just hide it anywhere where there is power source and you're essentially done and very hard to track.
Very easy to track... radio direction finding for a static source, even operating at low power output, is a solved problem. Adding a GSM uplink provides zero annonymity because you still need to connect via IP, which can ultimately be unpicked even with TOR or VPN masking if the infrastructure has been compromised.
The GSM modem will need a SIM card with your number on it to work. Unless you can obtain an anonymous one, but I believe that is almost impossible in most countries.
"The term mini-FM was first used in a mass-circulation newspaper in 1982, when a very low-watt FM-station movement started. Mini-FM stations have very little power judged by any standard-usually less than a hundred milliwatts. Although such a weak signal may seem to be of no use for broadcasting, the purpose was not broadcasting but narrowcasting.
The birth of mini-FM is related to the peculiar situation of radio in Japan. When mini-FM originated in the early 1980s, most cities in Japan had only one FM station, if any at all, because only government-operated stations could obtain licenses;station administrators tended to be retired government officials. The situation is not so different today, although there are seven stations in Tokyo now instead of two. In this constricted atmosphere many people wanted more open programming. Throughout the late 1960s and 1970s, we had become familiar with American popular and countercultures, since American films and records were easy to obtain. People were longing for diversity in culture yet there were no radio or television stations in Japan covering subcultures. When mini-FM started, therefore, it became a cultural craze."
At 100m-500m I'd guess the chances of zero people listening is quite high so seems almost like something done just for the sake of it? Bit of a dig a hole, fill it up type exercise?
Hyperlocal random discoverability is the missing ingredient. I guess the 2023 equivalent would be the local FB group. Or a QR code/url on a local (physical) bulletin board.
While limiting, if you're in a world city with huge population density you can still reach a lot of people. Suppose you live in a high rise, you can reach all the people in the buildings across from you, in the cafe down below, offices in the other building across from you, etc.
> You can extend and reduce it quite flexibly. I thought that the time has come when we can explore and experiment airwaves for molecular revolution and micro analysis. Radio will resonate the more micro and deeper side of the individuals. It will have message but it may be something to do with emotion and feeling.
Really liked this mysterious passage. Really interesting in the way physical resonance may be used as a way of expression
Is it what one could set up using a car-FM audio adaptor? I remember it was possible to pick someone's music on your car radio when waiting at the traffic light.
Peer-to-peer wifi technically could be an alternative path but is more binding and exposes MAC address and other details unlike FM which is mostly private for receiver.
I've pondered exactly this -- if they were suitably synchronized (which is doable using other stronger signals), they could even appear as "one transmitter" that just happens to have low signal strength across a very wide area.
You would need quite some buffering on the nodes, to keep them from losing sync if their internet connection hiccups for a moment, but also, losing one node shouldn't be a big deal if there's another one not too far away. So maybe you just tolerate this by having them turn themselves off until they regain sync.
The trick is convincing a whole bunch of node operators to broadcast a single stream instead of everybody transmitting their pet stream on the same frequency and then it fragments into traditional FM-capture islands of different signals.
Such multi-site, same frequency broadcasting setups are usually called Simulcast, and are still used for some public safety trunked radio systems in the U.S. The biggest issue with simulcasting is the need for extremely precise clock synchronization and the audio carrier generation, to the point where something like using a slightly different soundcard can result in massively distorted received audio due to the effects of FM doubling. Clock synchronization is usually achieved via GPS, there's a good number of off-the-shelf solutions available. But when it comes to the audio path, it's typical to use the exact same hardware across all sites because otherwise controlling for even the smallest of differences when attempting to troubleshoot becomes an huge hassle. At the beginning of this blog post[1] is a brief overview of some things to take into consideration when building a simulcast system.
Is this still an issue if it's low power nodes in a mesh network that has infrequent
overlap and a shared system that pre-emptively mitigates this with geolocation data?
If you don't do synchronization, then you just have a bunch of independent transmitters that're transmitting roughly the same program. -ish. Sorta.
Suppose you put an RDS/RBDS subcarrier under the audio, so receivers can display metadata or whatever. If a given receiver drives between transmitters, or if FM capture and phasing effects mean it's constantly bouncing between transmitters, then it corrupts the data frame(s) being transmitted at the time.
Or if the desynchronization is more than about 20ms or so, it can be audibly annoying to the listener, disorienting and unpleasant if it happens too often. (We've all probably experienced a phenomenon when creeping forward at a red light, the audio fades, and comes back, and fades again. Same effect, but imagine the program glitching back and forth a bit each time because every few inches, the capture effect switches sources.)
If you synchronize, then you have effectively one transmitter with a bunch of antennas. The program is exactly the same except for microsecond-level discontinuities when moving between transmitters, and that's not enough to corrupt either the subcarrier data or the audio. (In the creeping-forward scenario above, it would behave exactly like a normal radio station -- fading and restoring, but not glitching.)
Now, in Europe, they do the many-transmitters-same-audio thing, but they do 'em on different frequencies, and use RBDS to inform the receiver of all the alternate frequencies (AF list) carrying the same program. When RSSI on the current signal drops below a threshold, the receiver checks the others, then doublechecks their RBDS program identification (PI field) to make sure they really are the same program, then selects the strongest one and makes the switch. This only happens once in a while though, say 10-30 minutes as you drive through a valley, not several times a second, so the timing glitch isn't problematic.
FCC explicitly bans "broadcasting" for amateur ham radio. Transmissions are intended to be direct conversations except for when calling for contact and some carve outs (emergencies, etc). Scheduled nets are the closest allowable thing.
In the US you may broadcast FM with a Part 15 device limited to about 200 ft (61 meters.) However, finding such devices and transmitter ICs is becoming rare as this device market has mostly transitioned to Bluetooth. Low Power FM requires a FCC license and appears to be stagnant with no licenses granted since 2013.
34 comments
[ 3.3 ms ] story [ 90.8 ms ] threadPost-Covid, work from home, internet deliveries the trend is arguably things have to distribute to people now rather than people distribute to things.
FM radios have all but gone from modern cellphones and vanishingly few people are carrying around discrete ones. BT serves this physically local radio purpose now and is pretty much everyone has it on their person.
So it might have had a past but it doesn't seem to have a future.
Some phones released around the 2010s also had FM transmitters, for example the [Nokia N8](https://www.gsmarena.com/nokia_n8-3252.php). The use case for these was to be able to listen to the music you had in your phone via your car stereo, since AUX ports and BT sharing wasn't common back then.
https://www.gsmarena.com/results.php3?chkFMradio=selected
Tragically, this question illustrates how successful that Big Tech (Apple, Google, Facebook and the telcos etc.) has been in distorting the free-to-air broadcasting medium and redirecting listeners to its PAID services (Apple store etc.).
The fact that someone is actually unaware that essentially all mobile phones were capable of receiving FM Radio (the standard free-to-air FM broadcasts) until Big Tech nobbled them proves the point.
It's shocking this has happened and that government has dropped the regulatory ball. Traditional broadcasters are heavily regulated and have to pay substantial license fees yet the likes of Apple, Google etc. can do what they damn well like without impunity in the absence of any such regulation. (We only have to look at the damage to the social order these behemoth companies have caused in recent years to see that they have to be regulated).
That Big Tech has managed to essentially kill the FM service on phones to the extent that people aren't even aware of its existence shows that government has abrogated its regulatory responsibly. Moreover, I find it hard to understand why FM broadcasters haven't kicked up a huge stink over the neutering of the FM service, after all, it's in their interest that their broadcasts can be received on mobile devices.
It's high time this is rectified, a 20% tax or surcharge on every phone without FM enabled would solve the problem instantly. Government could easily justify this on the grounds that FM is a viable emergency service—when the internet goes down, FM would provide an emergency backup information service—one that it's already performed for over three-quarters of a century.
Is this in the same parallel universe I keep reading about where all modern phones don't have headphone jacks? Because every smartphone I've ever owned has had both.
small personal pirate radio stations are nothing new - my little brother ran one intermittently in the early 70s covering quite a bit of lincoln, uk. as this was broadcasting from very close to the then lincoln police hq, my dad eventually shut it down, with prejudice.
http://anarchy.translocal.jp/non-japanese/radiorethink.html
"The term mini-FM was first used in a mass-circulation newspaper in 1982, when a very low-watt FM-station movement started. Mini-FM stations have very little power judged by any standard-usually less than a hundred milliwatts. Although such a weak signal may seem to be of no use for broadcasting, the purpose was not broadcasting but narrowcasting.
The birth of mini-FM is related to the peculiar situation of radio in Japan. When mini-FM originated in the early 1980s, most cities in Japan had only one FM station, if any at all, because only government-operated stations could obtain licenses;station administrators tended to be retired government officials. The situation is not so different today, although there are seven stations in Tokyo now instead of two. In this constricted atmosphere many people wanted more open programming. Throughout the late 1960s and 1970s, we had become familiar with American popular and countercultures, since American films and records were easy to obtain. People were longing for diversity in culture yet there were no radio or television stations in Japan covering subcultures. When mini-FM started, therefore, it became a cultural craze."
20 years ago it would be cool, with a lot of people having some kind of FM receiver at hand but nowadays not really.
Really liked this mysterious passage. Really interesting in the way physical resonance may be used as a way of expression
Peer-to-peer wifi technically could be an alternative path but is more binding and exposes MAC address and other details unlike FM which is mostly private for receiver.
You would need quite some buffering on the nodes, to keep them from losing sync if their internet connection hiccups for a moment, but also, losing one node shouldn't be a big deal if there's another one not too far away. So maybe you just tolerate this by having them turn themselves off until they regain sync.
The trick is convincing a whole bunch of node operators to broadcast a single stream instead of everybody transmitting their pet stream on the same frequency and then it fragments into traditional FM-capture islands of different signals.
[1] - https://www.hamradiodx.net/building-a-simulcasting-voting-re...
Suppose you put an RDS/RBDS subcarrier under the audio, so receivers can display metadata or whatever. If a given receiver drives between transmitters, or if FM capture and phasing effects mean it's constantly bouncing between transmitters, then it corrupts the data frame(s) being transmitted at the time.
Or if the desynchronization is more than about 20ms or so, it can be audibly annoying to the listener, disorienting and unpleasant if it happens too often. (We've all probably experienced a phenomenon when creeping forward at a red light, the audio fades, and comes back, and fades again. Same effect, but imagine the program glitching back and forth a bit each time because every few inches, the capture effect switches sources.)
If you synchronize, then you have effectively one transmitter with a bunch of antennas. The program is exactly the same except for microsecond-level discontinuities when moving between transmitters, and that's not enough to corrupt either the subcarrier data or the audio. (In the creeping-forward scenario above, it would behave exactly like a normal radio station -- fading and restoring, but not glitching.)
Now, in Europe, they do the many-transmitters-same-audio thing, but they do 'em on different frequencies, and use RBDS to inform the receiver of all the alternate frequencies (AF list) carrying the same program. When RSSI on the current signal drops below a threshold, the receiver checks the others, then doublechecks their RBDS program identification (PI field) to make sure they really are the same program, then selects the strongest one and makes the switch. This only happens once in a while though, say 10-30 minutes as you drive through a valley, not several times a second, so the timing glitch isn't problematic.
And you’d no longer be limited to half a kilometer - to your existing peers.
https://www.fcc.gov/media/radio/low-power-radio-general-info...