Even as music streaming services and podcast apps dominate most of our listening time, it’s still a great idea to keep a radio on hand, if for nothing else than in emergency situations. After all, blizzards, hurricanes, and other natural disasters can quickly take out both home and mobile Internet access. If you’d like to have an FM radio with the absolute smallest footprint, take a look at this one built around an ESP32.
While the radio uses the ESP32 as the main control board hosted by a TTGO T-Display board which adds a 1.14 inch ST7789V IPS panel, it also makes use of the TEA5767 chip for handling the FM radio signals. As [Volos Projects] has it programmed, the ESP32 stores five preset channels which can be toggled using two buttons at the bottom of the device. There’s also some circuitry to handle output to headphones or a stereo.
For making the radio even smaller, some of the audio processing could be done on the ESP32 instead, although its much simpler to take a slightly larger footprint and offload this to an audio processing chip. Since the source code for this project is open, modifications could be done including adding seek/tune functionality instead of relying only on presets. If you’re not building this for emergencies, though, and your entire area is dominated by cookie cutter corporate-owned radio stations, an ESP32 with an internet connection is great for accessing better radio stations around the world.
Thanks to [Peter] for the tip!
Radio? It’s like browsing Internet without uBlock.
so true. even npr is sponsor-heavy these days.
I don’t wish to be disparaging as this project might get someone into electronics, programming or radio if aimed right, but the code here is very simple, it’s little more than a “hello world” program with two Arduino libraries. Personally I’d have aimed any coverage of this project specifically at beginners, maybe children.
now using the the radio tuner and ESP’s ADC, the next step would be to software decode DAB radio =)
https://github.com/pu2clr has nice libraries for all popular radio chips
I can also recommend https://github.com/mathertel/Radio which supports several radio chips. I added support for RDA5807FP I2S mode some months ago. So you can even read the digital audio signal from the chip to ESP32 and stream or filter it.
“Simple” home-brew FM broadcast receiver, 1960’s: A half-dozen sub-mini tubes and some LC circuitry. Tools required… soldering iron.
“Simple” home-brew FM broadcast receiver, 1970’s: A half-dozen transistors and some LC circuitry. Tools required… soldering iron.
“Simple” home-brew FM broadcast receiver, 2023: RAM, ROM, ALU, Sequence logic, digital display, freq synthesizer, etc etc.. implemented with a half-MILLION IC transistors on tiny epoxy IC black-boxes. Tools required… a billion transistors more, in the form of a laptop or desktop computer to run the dev software tool chain. Internet connection likely essential for initial setup
No criticism of the project…. Just pointing at the interesting and noteworthy change in definition, over time, for phrases like “simple” and “FM receiver.”
But in the 60s and 70s versions there are many times more atoms, atoms are complicated, so they must be more complicated.
You could always still build a crude FM radio. The thing about this project is that it introduces people to esp32, dev software etc in a very simple way which could lead to other projects. They aren’t billing this as “The simplest FM radio”
Point: Missed
Sure, and that’s great – but we’re on Hackaday, not Tutorialaday. Where’s the hack?
“Where’s the hack?”
Down the hall, second door on the left.
This…is so much work for a tool equaled by a $5 pocket radio from a garage sale.
See above. Sometimes the destination is less important than the trip
“.. This…is so much work for a tool equaled by a $5 pocket radio from a garage sale… ”
Welcome to the Hacking Community.. :)
Cap
Intro project for a esp32.
Yeah, you could just go out and buy a $5 pocket radio, but could you program it as an RC robot controller as well?
Whenever I bring home anything electronic from a garage sale (normally from the FREE pile not $5) the first thing I do is tear it apart so that I can put an ESP32 or a Pi in it.
This chip radio blob is probably what passes for FM in newer cars loaded with smarts. Trying to get weaker stations with one is just luck.
More bare electronics awaiting a spill or sweaty hands.
One fifth of the FM band in the US is noncommercial and many others in the rest of the band are too.
@Sword “FM radio with the absolute smallest footprint” Point: Missed
It’s most definitely not the smallest.
Relatively modern: The iPod Nano 6th gen included an FM radio.
Today, you can get this FM radio smaller than a lighter: https://www.walmart.com/ip/Mini-Pocket-FM-Radio-Rechargeable-Portable-76-108MHZ-Radio-Receiver-with-Backlight-LCD-Display-Wired-3-5mm-Headphones/
And going back to the 1980’s, my emergency kit I have a old UK-branded FM radio that’s about the same volume as a lighter that runs on 3 small coin cells – https://www.radiomuseum.org/r/mikes_mini_ukw_radio_ls8.html . For size tradeoffs, note the Off/Low/High combination power+volume switch.
Today, the main restrictions on “small” are battery and user interface. Hobbyist friendly connectors are decidedly NOT small. “Chip on board” where you integrate everything into a single chip is not just cheap, it’s also ultra compact. All you need is a foundry (and lots of money).
ideal situation when You see esp have to less keys.
5-16 is optimal
I built something similar “Dumb Smart Radio” to solve the problem of needing a FM receiver that I could power on and off with a simple mains switch (so it could go on and off with the rest of my xmas lights).
No-where near or wide could I find an fm receiver that would both fit in the waterproof enclosure *and* not be soft power buttoned… So I made one, it’s dumb cos it comes on when you give it power…. it’s smart cos it’s wifi controllable lol