Pi Pico Rx – A crystal radio for the digital age?

https://101-things.readthedocs.io/en/latest/radio_receiver.html

#HackerNews #PiPicoRx #crystalRadio #digitalAge #technology #innovation

"You NEED a Headset" – well, in 1925 you actually did if you wanted to listen to a radio, which weren't yet powerful enough to be heard via a speaker or horn.

#headphones #radio #SoundStudies #Brandes #CultureOfSound #CrystalRadio

Foxhole Radios date back to the 1890s but were most popular during WW2. Soldiers couldn't use vacuum tube radios bc their radio waves could be traced by the enemy, so soldiers built safe but crude crystal radios like this one at the Anzio beachhead in Italy in 1944, which used a blue steel razor blade with a pencil lead pressed against its surface by a safety pin as a detector.

Learn to make your own foxhole radio here:

https://survivalkit.com/blog/how-to-build-a-foxhole-radio/

#FoxholeRadio #Radio #CrystalRadio

The Simplest Way To Spot 2.4GHz RF

When the cool kids are showing off their SDRs it's easy to forget that a radio receiver can be very simple indeed. The crystal set is one of the earliest forms of radio receiver, a tuned circuit and a diode that would pick up those AM broadcast stations no problem. But lest you imagine that these receivers can only pick up those low frequencies, here's Hackaday alum [Ted Yapo] with a handy 2.4GHz receiver that picks up strong WiFi and microwave oven leakage.

It's about as simple as it gets, an LED with a UHF diode in reverse across it. The clever part lies in the wire leads, which are cut to resonate as a dipole at 2.4 GHz. The resulting RF voltage is rectified by the UHF diode, leaving enough DC for the LED to flash. If you are wondering why the LED alone couldn't do the job as a rectifier you would of course be on to something, however its much worse high frequency performance would make it not up to the job at this frequency.

The glory days of analogue broadcasting may now be in the past, but it's still possible to have fun with a more conventional crystal radio. If you are adventurous, you can even make one that works for the FM, band too.

#radiohacks #crystalradio #microwave #microwavedetector