I don’t see the necessity for FM Radio to be used for this. They’ve removed them from most of today’s phones, and adding them back would be just as complex as adding something like LoRa for emergency messages.
LoRa could also be used for mesh-messaging, and bring some added privacy features that people genuinely would have a use for.
I guarantee this article has FM Radio station money behind it.
I’m a qualified amateur radio operator and I work in IT as my day job, if you can’t see how bad it would be to continue to put all our eggs into one basket for datacom, primarily in the hands of poorly regulated private cellphone companies, then I can’t really help you.
Fact is, 80-110 MHz FM requires less infrastructure (aka fewer broadcast points) to more completely cover an area, and it’s almost impossible to have it blocked by buildings/walls/vehicles, etc. Sure, the signal might go to shit, but it’s at least able to be heard even in very challenging conditions. It also takes nearly no power to run. Receiver chips can be made so small that it would be a trivial addition to make for most cellular manufacturers. There’s no licensing fees or service fees so the entire process is free from top to bottom.
Add that to the fact that it’s already deployed, regulated and configured for emergencies, and you have a very low implementation cost for a very reliable and robust service.
The idea here isn’t to add it so we can listen to FM commercials all day. Anyone I know who had FM on their cellphone, didn’t use it; and I won’t suggest that anyone will use it now… but if there’s a major catastrophe and the cellular networks go down, having a recieve-only way of getting emergency information to those who are otherwise disconnected from everything is a big deal. A lot of households are going digital only for their entertainment and getting rid of old stereos and hi-fi units with radio built in for all HDMI systems that make their Netflix work nicely. Many also have zero land line service so once the internet stops functioning and the cell towers go out, the only method of communication these people will have is standing on their porch and screaming into the void.
I’ve monitored communications during major outages, like sitting hurricane hits on the contental US and heard the radio traffic stating that there’s people at x location and all consumer/commercial communication systems are inoperable. The only thing working was an amateur owned and operated repeater network to relay the communication across the region; I was listening to an internet relay on the outskirts of the coverage area and it was clear that they would have had no outbound communication if they didn’t have those repeater nets. Inbound, I’m sure FM and AM radio was still operable, so anyone with an FM set could hear news and alerts as they happened.
Radio is also nearly instant, while LoRA mesh networks rely on people having nodes to relay the messages and the messages may be interrupted while a node is down. The first isn’t a thing yet, the second is difficult to do at best. Amateur FM cells can transmit over many miles potentially several dozen, meanwhile most LoRA can’t reach a fraction of that far, requiring a massively larger number of them, and each one is a potential point of failure.
With regulation, commercial broadcast FM sites are required by law to participate in the emergency broadcast system, no such regulation exists for LoRA.
Under normal operating conditions, FM is fairly useless, unless you feel like listening to ads, but in an emergency, it can be the only way for you to be told that, though the weather seems to have gotten better, it’s temporary and you should stay where you are.
All my handheld radio transceivers have commercial FM recievers built in, so either way, I’m covered. I also have several dedicated FM and shortwave receiving radios around. I have adequate communication capability for an emergency. I’m not perfectly set up, even remotely, but I’ll be able to reach out to someone if I’m without power, internet, cellphone coverage, etc, during a major event. I can call for help, get information about the situation and it’s duration, I can reach out over 10 miles or more to communicate with others, all with my handheld.
And you want to take all this infrastructure and preparedness that we as a society have developed over more than a century, and flush it all away… because why? You have a hard-on for LoRA? You think old tech is useless in today’s day and age? Because you have a problem with broadcast radio trying to survive, a service that’s free to you, by playing ads?
Most people won’t read until that last paragraph, ha ha.
Thanks for writing this up. I have always been concerned that my car is the nearest FM radio. I always kept a clock radio stashed in my basement “workshop” area but it was thrown out at some point along with the old rotary phone I had with it.
My son has a beginner electronics kit that can build a very low powered transmitter so I got him a cheap usb chargeable AM/FM receiver with an aux in, speaker, and headphone jack for next to nothing. The antenna is actually extendable and doesn’t suck. Going to stash it when he’s done with it. Could come in handy.
I always did but we moved across country as a lot of stuff just got tossed. You know that old radio in the garage covered in paint, and the clock radios no one uses anymore, etc. My mother’s house has one in every room, I think (except bathrooms and maybe the living room, ironically).
I would like to be the first to encourage you on that journey.
For me, I’ve mainly focused on skills, more than stuff. IMO, preppers are a bit short sighted most of the time, they’ll pack a month’s worth of supplies in an airtight drum and leave it in their garage. It’s 50+ lbs of stuff. You’re telling me that when you get an evacuation order, you’re going to haul that thing into you Ford Explorer before you evacuate, when there may be a flood or wildfire just minutes from you? Okay.
I have my first aid certificate. Standard first aid, level c CPR and AED training. I also know some basic self defense (though it’s been years since I practiced anything), and I know enough about radio that if I’m presented with a walkie or ham radio, or something, I know what I’m doing without being told (maybe if I find one and the previous owner of the radio is incapacitated or something).
I’ve put a first aid kit everywhere I practically can, we have two in the house, plus one in my car (soon to be all cars). I also want to look into some MRE’s and a safe way to store a moderate amount of water long term in my car (winters here are kind of a shit show)… plus maybe some basic survival supplies, enough to make a fire and a crude shelter, which can be repurposed for other things as well. Maybe a water filter for turning Creek water into drinkable/potable water… I want to keep it fairly trim. For shelter supplies, a good multipurpose knife, a couple of tarps and some good rope… you get the idea. Though, that stuff sounds like things you would carry to kidnap and murder someone. Not my intent, but it’s funny how much overlap there is between survival gear and gear for more nefarious activities…
I’m also very well learned on how to fix just about any common thing, like cars or something, so I should be pretty useful in a pinch. I have a ham radio in my car with more range than the walkies I have, and I have a small collection of walkies all with extra batteries charged and ready to fly (usually already attached to my backpack which is my usual daily carry). I need to make some tweaks and round out my setup (as previously mentioned), but I feel like I’m in a good spot for now.
I think FM Broadcast is great, but with regard to phones aren’t we missing something here?
For a phone to even receive FM broadcast headphones have to be plugged in, it’s been a requirement for any FM RX capable phone I’ve ever had, for antenna purposes.
So with regard to the argument for mobiles to have FMrx if such functionality were to become common place we’d need to see the return of headphone jacks and people would need to be carrying corded headphones for it to function.
I think this capability is a great idea, but the limitations forced on us by losing the headphones socket as well as societys fascination with making everything wireless at any cost is a little concerning.
I’ve always considered average to good quality wired buds to be great, but it seems they really are on their way out.
You have an excellent point, and historically, yes, you did need something plugged into a headphone jack to facilitate the rx of the transmission, however, this isn’t strictly required. Broadcast FM is in the 2-3m range, meaning a full-wavelength antenna would be aproximately 3m in length, we don’t even see this on vehicles; most are limited to less than 1m. Even with aerial whip antennas for home-based hifi/stereo systems, often the antenna is not any longer than 1m/3ft, which is about 1/3rd as long as it should be for optimal signal.
The issue here isn’t one of having the space for the antenna, since smaller antennas are used in all sorts of applications, such as with FM and vehicles/stereos etc. The issue is having enough antenna to produce a signal strong enough to differentiate from background noise. The signal to noise ratio is key here. Historically, the only good way to get more signal is to use a better tuned, larger antenna, or an array of the same, this isn’t so much the case anymore. There’s plenty of antenna designs that are still fairly omnidirectional, that can enhance signals. Combine that with more advanced filtering and pre-amplification, a large antenna is not generally a requirement anymore; even the 1m/3ft whips used on cars are often overkill for what we can do with signal processing and modern design. Look at any modern vehicle, and with few exceptions, there’s no longer a visible antenna. That’s not because there isn’t an antenna for FM, it’s because the technology has progressed enough to be able to use much smaller antennas to accomplish the same task. The antennas are still there, they’re just so small and well placed that you don’t need a flagpole on your hood or trunk lid to have it work as-well-as any other FMrx antenna.
Given that the proposal requires a minor redesign of the cellphones to incorporate the broadcast receiving radio, adding a small antenna, or simply using the chassis of the phone as an antenna, would not only be possible but it should be fairly trivial to accommodate for. by no means am I saying it would be the worlds greatest FM antenna system, most certainly it would not be, but it should be sufficient to differentiate the signal from the noise; with relatively trivial signal processing, it should be more than adequate for the purpose.
The technology surrounding FM broadcast radio didn’t just cease and we get what we get; vehicles, among other specific technologies still utilize FM radios and development has continued on them even though very few people have been watching. The technology is far improved from what you can build with a battery, coil of wire, a speaker, and a handful of resistors/capacitors/etc. and similarly it’s far improved from what vehicles had even 15 years ago. Add that to the fact that radio technology is all pretty much the same across the board (from what we use for broadcast FM, to WiFi, 4G/5G/LTE cellular, and GPS included), and a lot of the developments made in any area of radio can be almost directly translated to another radio on a different band, and there’s a lot of technology that, unsurprisingly, will blow most of what most of us have in our houses on our hi-fi stereos, out of the water.
The wonderful thing is that a lot of it is tied to miniaturization and modernization of the technology, meaning a lot of this is tied into integrated circuits that are being mass produced already. IC designs that can be embedded into other ICs to decrease the overall number of chips in a device, fairly easily.
The point I’m dancing around is software-defined radios. SDR is becoming a huge player in all aspects of radio technology, and can replace far more advanced/complex systems with something less complex than a raspberry pi, and often less costly. The big cost of SDRs is mainly regarding transmission, since they don’t put out a very strong signal, and need some significant and high-quality amplification to be useful; but we’ve seen SDR chipsets starting to dominate the lower-cost market within the HAM/Amateur radio space. Extremely capable, very small and power efficient radios, for significantly less cost than more traditional methods of doing the same. The issue is that first word: Software. With great software comes great responsibility… or something. Fact is there’s a lot of SDR radios out there with garbage software interfaces… at least there are right now. Things are improving all the time. The wonderful thing about SDR, is that they’re generally compatible with whatever you want to use them for… meaning AM/FM, or even something more elaborate like OFDM, or other modulation techniques. This means these radios can essentially be re-programmed on the fly to adapt to a new standard with little more than a software update.
I apologize for the long discussion on this, but the technology is so interesting to me the more you look at it. Yes, antennas are important, but not nearly as important as they were even 10-15 years ago.
s; most are limited to less than 1m. Even with aerial whip antennas
Wavelength varies from 2.7 to 3.4 metres.
Just because that is the size of the wave doesn’t meant that a good antenna has to be that size.
A very good basic antenna is a 1/4 wave vertical, and we see them pretty often as telescopic antennas on radios and cars.
A 1/4 wave FM broadcast antenna will perform excellently, and will be 68cm to 85cm in length.
More modern cars have antennas printed into a window similar to a demister strip.
They are actually NOT smaller, some can be quite larve, but also very stealth.
But the point remains is that they are NOT small as you suggest.
Much shorter antennas exist, but there is a gain penalty, and that penalty gets more extreme the smaller the antenna gets.
I have such a small antenna on my car and it IS an issue.
In physics nothing is free, yes, you can make an antenna small and still have it be resonant, but you’ll pay a price on effective gain.
This is a problem that technology has not solved.
Sure, clever designs have helped a little, but there is always a price to pay if you try to cheat the physics.
A compromised antenna can work in a very very stong signal area, but it will easily be the difference between a clear solid recieve and no recieve at all in a fringe area.
AM Broadcast is an example of this, with antennas sometimes 2 inches / 50mm long or even less and hidden inside the radio.
Buy as a ham myself with a HF setup, even my HF setup, which is a poor compromise on MF broadcast gets me stations from all over Australia.
That isn’t going to happen with a regular AM receiver.
Ultimately, sure you can have a mobile with no external antenna receive FM broadcast… but only in a VERY VERY strong signal area, within a few miles of the transmitter, while a propper antenna will work at 10x the distance.
Given that the proposal requires a minor redesign of the cellphones to incorporate the broadcast receiving radio, adding a small antenna, or simply using the chassis of the phone as an antenna, would not only be possible but it should be fairly trivial to accommodate for. by no means am I saying it would be the worlds greatest FM antenna system, most certainly it would not be, but it should be sufficient to differentiate the signal from the noise
This would work at very short distance only, it really would be that limited.
Would it be useful for the people in those short distances? Maybe.
Buy while a regular ordinary transistor radio with a telescopic antenna would work 10-30x further away, comparing those 2 really shows how much of a compromise is going on.
The point I’m dancing around is software-defined radios.
The big cost of SDRs is mainly regarding transmission, since they don’t put out a very strong signal
This is true for any radio type ever, it’s not an SDR specific thing.
EVERY radio that puts out more than a few dbm needs some level of amplification.
This is NOT and SDR specific thing.
It might appear that way because fo how many affordable SDRs just come with a low output.
This is just a normal Monday for any radio system from a $50 CB to a broadcast station, SDR or not.
SDR’s are not magic.
In fact they actually have some drawbacks compared to conventional designs with regards dynamic rage, over loading etc…
Pulling the ‘SDR’ card and not knowing this i think shows your lack of understanding of the topic (not trying to diss, just an observation).
SDR’s are a great tool, i have 4 of them in front of me as i type this, so I’m no stranger.
Icom IC-705, Icom IC-7300, HackRF and an RTL-SDR.
You could also maybe count the University of Twente webSDR i have open in another tab, and an MMDVM at a stretch to make it 6.
http://websdr.ewi.utwente.nl:8901/
This is all exciting stuff… but none of it has revolutionised RF physics for human portable commodity radios, nor even come close to an adjacent technology that could be adopted / adapted.
My ~ AUD$1900 IC-705 can go from picking up stations all over the state of Victoria, Australia with it’s non optimal antenna tuned for 146MHz, to picking up literally nothing if i hook up a few hundred mm of wire to it’s antenna socket on the bench here.
And I can engage pass band filtering, up to 2 pre-amp stages, and a variety of Digital Signal Processing features and sill get… nothing.
I appreciate your passiona nd interest, but… physics.
We can look at other technologies that are great…
WiFi… it’s great, but the transmitter location is in your home and still struggles to cover some larger homes… from inside your home itself.
Cellular… again, great, but again, as the name implies it;s made up of ‘cells’, physics is a massive issue with cellular, each individual cell tower consists of tens or sometimes hundreds of transceivers, each connected to phased arrays of hundreds to thousands of antenna elements… and that’s just a single site, many towns will need multiple of these for coverage. Cell is not immune to the limitations of physics, and it has to brute force the situation from the tower end so as we can have small devices in out pockets… and even with all that i get no coverage int he middle of my local supermarket.
Do an image search for ‘cell panel antenna inside’ and see if you can find a picture fo the actual antenna elements, my results mostly got the rear so you might have to scroll a bit.
A lot of the modernisation you refer to is just that given the value we place on connectivity while remaining portable the effort has shifted to needing to bring the signals closer to the user. Looking at that broadly, while some gains have been made what’s really happened is that the signal has been bought closer to you, making you think magic has happened.
Yes, antennas are important, but not nearly as important as they were even 10-15 years ago.
I couldn’t disagree more.
The antenna is the single most significant component of any system.
I think the best demonstration of this is modern cellular as it shows what has been needed to be done to bring connectivity top the masses and proves there is no way around.
That class of emergency radio is usually shortwave/am/FM. I have a shortwave/am/FM unit but it’s not hand cranked. The one we have is a ccrane, and honestly I’m not sure if that’s all that good. It seems to function, from the few times we’ve turned it on. I’ve never had to replace the batteries yet so that’s a plus.
Not sure on this. I’m prepared for disaster but I’m not what someone would call a prepper. I mostly have VHF/UHF ham radios and the knowledge on how to make use of them. I’m still pretty new, so I hope someone can comment further.
The ccrane was my late father’s. He insisted on buying that brand and I’m not sure why. It’s probably about 10 years old right now. It’s only a reciever, so anyone should be able to buy one.
A lot of people still have am/FM gear, and they’re so invested into their primary communications which is so reliable they don’t think about secondary communications. I have, which is why I’m a ham operator.
Most people at least have FM in their car, the broadcast range is in the lower VHF airspace, not much higher than HF. Most of the HF and LF bands are so tightly allocated that there’s no room to just Willy nilly add another frequency for emergency use for civvies… which would require everyone to buy new radios, which they won’t. Meanwhile, there’s still shortwave, which people also don’t buy that’s already there and lower on the frequency range than broadcast FM… people need to be saved from themselves. Allocating something new and building a bunch of new infrastructure for it is idiotic. The structure is already there with broadcast FM, we just need to save people from themselves and ensure that they have access to it.
I’d be in favour of there being a dedicated broadcast FM frequency for emergencies only. It would become trivial to have a radio station change frequencies to the emergency broadcast frequency when something happens. We could even make the frequency digital instead of FM, and have it encode information by text, and turn it into a recieve-only text-based emergency channel… but making it a whole new band and new radio type on a different frequency that’s not already set up for such a thing is insane to me. So much infrastructure cost for something we literally already have.
Any government that green lights such a program has lost the plot. Use what works.
in most cases radio is supported by SoC but disabled by software + headlhone jack is no longer wired up as anthenna (some phones don’t have headphone jacks at all nowadays)
I don’t see the necessity for FM Radio to be used for this. They’ve removed them from most of today’s phones, and adding them back would be just as complex as adding something like LoRa for emergency messages.
LoRa could also be used for mesh-messaging, and bring some added privacy features that people genuinely would have a use for.
I guarantee this article has FM Radio station money behind it.
I’m a qualified amateur radio operator and I work in IT as my day job, if you can’t see how bad it would be to continue to put all our eggs into one basket for datacom, primarily in the hands of poorly regulated private cellphone companies, then I can’t really help you.
Fact is, 80-110 MHz FM requires less infrastructure (aka fewer broadcast points) to more completely cover an area, and it’s almost impossible to have it blocked by buildings/walls/vehicles, etc. Sure, the signal might go to shit, but it’s at least able to be heard even in very challenging conditions. It also takes nearly no power to run. Receiver chips can be made so small that it would be a trivial addition to make for most cellular manufacturers. There’s no licensing fees or service fees so the entire process is free from top to bottom.
Add that to the fact that it’s already deployed, regulated and configured for emergencies, and you have a very low implementation cost for a very reliable and robust service.
The idea here isn’t to add it so we can listen to FM commercials all day. Anyone I know who had FM on their cellphone, didn’t use it; and I won’t suggest that anyone will use it now… but if there’s a major catastrophe and the cellular networks go down, having a recieve-only way of getting emergency information to those who are otherwise disconnected from everything is a big deal. A lot of households are going digital only for their entertainment and getting rid of old stereos and hi-fi units with radio built in for all HDMI systems that make their Netflix work nicely. Many also have zero land line service so once the internet stops functioning and the cell towers go out, the only method of communication these people will have is standing on their porch and screaming into the void.
I’ve monitored communications during major outages, like sitting hurricane hits on the contental US and heard the radio traffic stating that there’s people at x location and all consumer/commercial communication systems are inoperable. The only thing working was an amateur owned and operated repeater network to relay the communication across the region; I was listening to an internet relay on the outskirts of the coverage area and it was clear that they would have had no outbound communication if they didn’t have those repeater nets. Inbound, I’m sure FM and AM radio was still operable, so anyone with an FM set could hear news and alerts as they happened.
Radio is also nearly instant, while LoRA mesh networks rely on people having nodes to relay the messages and the messages may be interrupted while a node is down. The first isn’t a thing yet, the second is difficult to do at best. Amateur FM cells can transmit over many miles potentially several dozen, meanwhile most LoRA can’t reach a fraction of that far, requiring a massively larger number of them, and each one is a potential point of failure.
With regulation, commercial broadcast FM sites are required by law to participate in the emergency broadcast system, no such regulation exists for LoRA.
Under normal operating conditions, FM is fairly useless, unless you feel like listening to ads, but in an emergency, it can be the only way for you to be told that, though the weather seems to have gotten better, it’s temporary and you should stay where you are.
All my handheld radio transceivers have commercial FM recievers built in, so either way, I’m covered. I also have several dedicated FM and shortwave receiving radios around. I have adequate communication capability for an emergency. I’m not perfectly set up, even remotely, but I’ll be able to reach out to someone if I’m without power, internet, cellphone coverage, etc, during a major event. I can call for help, get information about the situation and it’s duration, I can reach out over 10 miles or more to communicate with others, all with my handheld.
And you want to take all this infrastructure and preparedness that we as a society have developed over more than a century, and flush it all away… because why? You have a hard-on for LoRA? You think old tech is useless in today’s day and age? Because you have a problem with broadcast radio trying to survive, a service that’s free to you, by playing ads?
Do you realize how stupid you sound?
Most people won’t read until that last paragraph, ha ha.
Thanks for writing this up. I have always been concerned that my car is the nearest FM radio. I always kept a clock radio stashed in my basement “workshop” area but it was thrown out at some point along with the old rotary phone I had with it.
My son has a beginner electronics kit that can build a very low powered transmitter so I got him a cheap usb chargeable AM/FM receiver with an aux in, speaker, and headphone jack for next to nothing. The antenna is actually extendable and doesn’t suck. Going to stash it when he’s done with it. Could come in handy.
Man, we have maybe 5 radios all around the house so battery operated or rechargeable.
I always did but we moved across country as a lot of stuff just got tossed. You know that old radio in the garage covered in paint, and the clock radios no one uses anymore, etc. My mother’s house has one in every room, I think (except bathrooms and maybe the living room, ironically).
Well this was a fun read and makes me want to be better prepared for a potential real emergency.
I would like to be the first to encourage you on that journey.
For me, I’ve mainly focused on skills, more than stuff. IMO, preppers are a bit short sighted most of the time, they’ll pack a month’s worth of supplies in an airtight drum and leave it in their garage. It’s 50+ lbs of stuff. You’re telling me that when you get an evacuation order, you’re going to haul that thing into you Ford Explorer before you evacuate, when there may be a flood or wildfire just minutes from you? Okay.
I have my first aid certificate. Standard first aid, level c CPR and AED training. I also know some basic self defense (though it’s been years since I practiced anything), and I know enough about radio that if I’m presented with a walkie or ham radio, or something, I know what I’m doing without being told (maybe if I find one and the previous owner of the radio is incapacitated or something).
I’ve put a first aid kit everywhere I practically can, we have two in the house, plus one in my car (soon to be all cars). I also want to look into some MRE’s and a safe way to store a moderate amount of water long term in my car (winters here are kind of a shit show)… plus maybe some basic survival supplies, enough to make a fire and a crude shelter, which can be repurposed for other things as well. Maybe a water filter for turning Creek water into drinkable/potable water… I want to keep it fairly trim. For shelter supplies, a good multipurpose knife, a couple of tarps and some good rope… you get the idea. Though, that stuff sounds like things you would carry to kidnap and murder someone. Not my intent, but it’s funny how much overlap there is between survival gear and gear for more nefarious activities…
I’m also very well learned on how to fix just about any common thing, like cars or something, so I should be pretty useful in a pinch. I have a ham radio in my car with more range than the walkies I have, and I have a small collection of walkies all with extra batteries charged and ready to fly (usually already attached to my backpack which is my usual daily carry). I need to make some tweaks and round out my setup (as previously mentioned), but I feel like I’m in a good spot for now.
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I think FM Broadcast is great, but with regard to phones aren’t we missing something here? For a phone to even receive FM broadcast headphones have to be plugged in, it’s been a requirement for any FM RX capable phone I’ve ever had, for antenna purposes. So with regard to the argument for mobiles to have FMrx if such functionality were to become common place we’d need to see the return of headphone jacks and people would need to be carrying corded headphones for it to function.
I think this capability is a great idea, but the limitations forced on us by losing the headphones socket as well as societys fascination with making everything wireless at any cost is a little concerning.
I’ve always considered average to good quality wired buds to be great, but it seems they really are on their way out.
You have an excellent point, and historically, yes, you did need something plugged into a headphone jack to facilitate the rx of the transmission, however, this isn’t strictly required. Broadcast FM is in the 2-3m range, meaning a full-wavelength antenna would be aproximately 3m in length, we don’t even see this on vehicles; most are limited to less than 1m. Even with aerial whip antennas for home-based hifi/stereo systems, often the antenna is not any longer than 1m/3ft, which is about 1/3rd as long as it should be for optimal signal.
The issue here isn’t one of having the space for the antenna, since smaller antennas are used in all sorts of applications, such as with FM and vehicles/stereos etc. The issue is having enough antenna to produce a signal strong enough to differentiate from background noise. The signal to noise ratio is key here. Historically, the only good way to get more signal is to use a better tuned, larger antenna, or an array of the same, this isn’t so much the case anymore. There’s plenty of antenna designs that are still fairly omnidirectional, that can enhance signals. Combine that with more advanced filtering and pre-amplification, a large antenna is not generally a requirement anymore; even the 1m/3ft whips used on cars are often overkill for what we can do with signal processing and modern design. Look at any modern vehicle, and with few exceptions, there’s no longer a visible antenna. That’s not because there isn’t an antenna for FM, it’s because the technology has progressed enough to be able to use much smaller antennas to accomplish the same task. The antennas are still there, they’re just so small and well placed that you don’t need a flagpole on your hood or trunk lid to have it work as-well-as any other FMrx antenna.
Given that the proposal requires a minor redesign of the cellphones to incorporate the broadcast receiving radio, adding a small antenna, or simply using the chassis of the phone as an antenna, would not only be possible but it should be fairly trivial to accommodate for. by no means am I saying it would be the worlds greatest FM antenna system, most certainly it would not be, but it should be sufficient to differentiate the signal from the noise; with relatively trivial signal processing, it should be more than adequate for the purpose.
The technology surrounding FM broadcast radio didn’t just cease and we get what we get; vehicles, among other specific technologies still utilize FM radios and development has continued on them even though very few people have been watching. The technology is far improved from what you can build with a battery, coil of wire, a speaker, and a handful of resistors/capacitors/etc. and similarly it’s far improved from what vehicles had even 15 years ago. Add that to the fact that radio technology is all pretty much the same across the board (from what we use for broadcast FM, to WiFi, 4G/5G/LTE cellular, and GPS included), and a lot of the developments made in any area of radio can be almost directly translated to another radio on a different band, and there’s a lot of technology that, unsurprisingly, will blow most of what most of us have in our houses on our hi-fi stereos, out of the water.
The wonderful thing is that a lot of it is tied to miniaturization and modernization of the technology, meaning a lot of this is tied into integrated circuits that are being mass produced already. IC designs that can be embedded into other ICs to decrease the overall number of chips in a device, fairly easily.
The point I’m dancing around is software-defined radios. SDR is becoming a huge player in all aspects of radio technology, and can replace far more advanced/complex systems with something less complex than a raspberry pi, and often less costly. The big cost of SDRs is mainly regarding transmission, since they don’t put out a very strong signal, and need some significant and high-quality amplification to be useful; but we’ve seen SDR chipsets starting to dominate the lower-cost market within the HAM/Amateur radio space. Extremely capable, very small and power efficient radios, for significantly less cost than more traditional methods of doing the same. The issue is that first word: Software. With great software comes great responsibility… or something. Fact is there’s a lot of SDR radios out there with garbage software interfaces… at least there are right now. Things are improving all the time. The wonderful thing about SDR, is that they’re generally compatible with whatever you want to use them for… meaning AM/FM, or even something more elaborate like OFDM, or other modulation techniques. This means these radios can essentially be re-programmed on the fly to adapt to a new standard with little more than a software update.
I apologize for the long discussion on this, but the technology is so interesting to me the more you look at it. Yes, antennas are important, but not nearly as important as they were even 10-15 years ago.
Wavelength varies from 2.7 to 3.4 metres. Just because that is the size of the wave doesn’t meant that a good antenna has to be that size. A very good basic antenna is a 1/4 wave vertical, and we see them pretty often as telescopic antennas on radios and cars. A 1/4 wave FM broadcast antenna will perform excellently, and will be 68cm to 85cm in length. More modern cars have antennas printed into a window similar to a demister strip. They are actually NOT smaller, some can be quite larve, but also very stealth. But the point remains is that they are NOT small as you suggest. Much shorter antennas exist, but there is a gain penalty, and that penalty gets more extreme the smaller the antenna gets. I have such a small antenna on my car and it IS an issue. In physics nothing is free, yes, you can make an antenna small and still have it be resonant, but you’ll pay a price on effective gain.
This is a problem that technology has not solved. Sure, clever designs have helped a little, but there is always a price to pay if you try to cheat the physics.
A compromised antenna can work in a very very stong signal area, but it will easily be the difference between a clear solid recieve and no recieve at all in a fringe area.
AM Broadcast is an example of this, with antennas sometimes 2 inches / 50mm long or even less and hidden inside the radio. Buy as a ham myself with a HF setup, even my HF setup, which is a poor compromise on MF broadcast gets me stations from all over Australia. That isn’t going to happen with a regular AM receiver.
Ultimately, sure you can have a mobile with no external antenna receive FM broadcast… but only in a VERY VERY strong signal area, within a few miles of the transmitter, while a propper antenna will work at 10x the distance.
This would work at very short distance only, it really would be that limited. Would it be useful for the people in those short distances? Maybe. Buy while a regular ordinary transistor radio with a telescopic antenna would work 10-30x further away, comparing those 2 really shows how much of a compromise is going on.
SDR’s are not magic. In fact they actually have some drawbacks compared to conventional designs with regards dynamic rage, over loading etc… Pulling the ‘SDR’ card and not knowing this i think shows your lack of understanding of the topic (not trying to diss, just an observation). SDR’s are a great tool, i have 4 of them in front of me as i type this, so I’m no stranger. Icom IC-705, Icom IC-7300, HackRF and an RTL-SDR. You could also maybe count the University of Twente webSDR i have open in another tab, and an MMDVM at a stretch to make it 6. http://websdr.ewi.utwente.nl:8901/
This is all exciting stuff… but none of it has revolutionised RF physics for human portable commodity radios, nor even come close to an adjacent technology that could be adopted / adapted.
My ~ AUD$1900 IC-705 can go from picking up stations all over the state of Victoria, Australia with it’s non optimal antenna tuned for 146MHz, to picking up literally nothing if i hook up a few hundred mm of wire to it’s antenna socket on the bench here. And I can engage pass band filtering, up to 2 pre-amp stages, and a variety of Digital Signal Processing features and sill get… nothing.
I appreciate your passiona nd interest, but… physics.
We can look at other technologies that are great… WiFi… it’s great, but the transmitter location is in your home and still struggles to cover some larger homes… from inside your home itself. Cellular… again, great, but again, as the name implies it;s made up of ‘cells’, physics is a massive issue with cellular, each individual cell tower consists of tens or sometimes hundreds of transceivers, each connected to phased arrays of hundreds to thousands of antenna elements… and that’s just a single site, many towns will need multiple of these for coverage. Cell is not immune to the limitations of physics, and it has to brute force the situation from the tower end so as we can have small devices in out pockets… and even with all that i get no coverage int he middle of my local supermarket. Do an image search for ‘cell panel antenna inside’ and see if you can find a picture fo the actual antenna elements, my results mostly got the rear so you might have to scroll a bit.
A lot of the modernisation you refer to is just that given the value we place on connectivity while remaining portable the effort has shifted to needing to bring the signals closer to the user. Looking at that broadly, while some gains have been made what’s really happened is that the signal has been bought closer to you, making you think magic has happened.
Whats a good emergency radio with a hand crank that you would recommend?
That class of emergency radio is usually shortwave/am/FM. I have a shortwave/am/FM unit but it’s not hand cranked. The one we have is a ccrane, and honestly I’m not sure if that’s all that good. It seems to function, from the few times we’ve turned it on. I’ve never had to replace the batteries yet so that’s a plus.
Not sure on this. I’m prepared for disaster but I’m not what someone would call a prepper. I mostly have VHF/UHF ham radios and the knowledge on how to make use of them. I’m still pretty new, so I hope someone can comment further.
The ccrane was my late father’s. He insisted on buying that brand and I’m not sure why. It’s probably about 10 years old right now. It’s only a reciever, so anyone should be able to buy one.
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reddit moment
A lot of people still have am/FM gear, and they’re so invested into their primary communications which is so reliable they don’t think about secondary communications. I have, which is why I’m a ham operator.
Most people at least have FM in their car, the broadcast range is in the lower VHF airspace, not much higher than HF. Most of the HF and LF bands are so tightly allocated that there’s no room to just Willy nilly add another frequency for emergency use for civvies… which would require everyone to buy new radios, which they won’t. Meanwhile, there’s still shortwave, which people also don’t buy that’s already there and lower on the frequency range than broadcast FM… people need to be saved from themselves. Allocating something new and building a bunch of new infrastructure for it is idiotic. The structure is already there with broadcast FM, we just need to save people from themselves and ensure that they have access to it.
I’d be in favour of there being a dedicated broadcast FM frequency for emergencies only. It would become trivial to have a radio station change frequencies to the emergency broadcast frequency when something happens. We could even make the frequency digital instead of FM, and have it encode information by text, and turn it into a recieve-only text-based emergency channel… but making it a whole new band and new radio type on a different frequency that’s not already set up for such a thing is insane to me. So much infrastructure cost for something we literally already have.
Any government that green lights such a program has lost the plot. Use what works.
73
73 to all on frequency.
in most cases radio is supported by SoC but disabled by software + headlhone jack is no longer wired up as anthenna (some phones don’t have headphone jacks at all nowadays)
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Thanks for the support gayhitler.
The broadcasters lobbied to have it mandated. Thats the only reason it was ever included.