FCC asks Apple to activate the iPhone’s hidden FM radio to aid public safety | Hacker News Reader

FCC asks Apple to activate the iPhone’s hidden FM radio to aid public safety

theverge.com

32 pointsmakmanalp12 comments

What is wrong with Ajit Pai? Has he no engineering background at all? It's like complaining that not all the bolt holes in my car have bolts in them because the same chassis was intended for different models.

This headline could just as well be, "FCC asks Apple to use some un-connected transistors". There's more to a radio than the heterodyne or nowadays receiver module. Antenna design, amplifiers, etc...

Like everything in this government, they recite news stories without verification. Pai refers to a Sun-Sentinel editorial that stated that all iPhones possess a software switch that could enable immediate use of the FM radio. From the editorial, "But Apple refuses to flip the switch that would let the iPhone work like an FM radio."

http://www.sun-sentinel.com/opinion/editorials/fl-op-editori...

Apple has stated there is no such switch in older phones and newer phones do not possess those chips.

Is there any proof that there is not an "FM" module? I saw the verge article, and the daringfireball, but neither of those writers are technical writers. A baseband radio, on any cellular device does FM modulation for the QAM/QPSK symbol decoding at base frequencies that would handily cover the FM band. Of course this may still not be possible due to the baseband processor's capabilities, but I'd like some technical data that proves this.

Look up the Qualcomm MDM modems of recent history and similarly for Intel / Infineon.

People that can buy a $1000 phone can’t afford a $4 FM radio, is that what they’re saying? Besides, Apple already gave you an emergency flashlight, don’t get greedy.

The likelihood is that the iPhone user will most likely be carrying only the Apple device when the catastrophe strikes.

Just wondering: would Apple be open to including FM radio in the iPhone 9 or whatever their next phone will be?

If it's for public safety, don't cell phones already have a feature designed specifically for that purpose (Cell Broadcast), which works even when the user doesn't have a wired headphone plugged into the device?

To make a guess: Could "FM sender + charged phone" vs "cellular network + charged phone" availability be a relevant distinction?

I.e. Fm sender + Cell broadcast -> better bet hedging.

I've never seen an iPhone displaying a CB message. Our mobile operator uses channel 50 to advertise network discounts, and iPhones don't display this, while many other phones do.

Does CB messaging work on iPhones?

Apple has never shied away from one of their product cannibalizing the market for another. FM radio though is on the way out, it’s obsolete. I doubt Apple is going to support it. Especially now that they quit supporting headphone cables which typically are used as the antenna for FM radios in phones.

Speaking of using headphones as antennas--are there any articles or documentation on how they work? Would you be able to replicate that on a PC, or does it need to use other some of the other antennas on the phone to function?

Most any bit of "random wire" should work for receiving FM (in quotes because "random wire" has specific meaning amongst some; in contrast to wire that has a specific length for the frequency). IOW, without having ever looked up the specifics, the two wires going to your ears act as a dipole antenna. Now, would a piece of wire cut specifically to receive FM frequencies do better? Certainly, back in the early days it was common to hook your new tube FM receiver to your TV antenna. That antenna was just a directional Yagi, and FM isn't very far away from TV (in fact, you can pick up TV channel 6 on FM if your receiver goes low enough). EDIT: after doing a bit of math, an optimal FM antenna would be around 36 inches or so. Take a set of headphones with about 18 inches on each side, and hey, you've got a pretty-close-to-optimal FM antenna. Could be coincidence, could be by-design, dunno.

In summary, yes, you could replicate this on a PC using a couple of pieces of wire you have rattling around your toolbox.

Reply on news.ycombinator.com