Years ago, people figured out Raspberry Pi’s can accidentally double as FM radio transmitters without a need for any radio front-end (if we don’t count a single jumper wire working as an antenna). They achieved this by tying a GPIO pin to a software-controlled clock around 100 MHz to modulate audio. This created a low-powered FM radio transmitter. Due to the pin producing a square wave instead of a neat sine wave, it also emitted weaker harmonics at 300MHz, 500MHz, etc., but any basic FM radio could pick up the audio. I wondered if a similar feat could be achieved by much less powerful Raspberry Pi Pico microcontrollers.
成立超过百年的松下集团，把昔日最赚钱的业务交给了中国公司。
。safew官方版本下载是该领域的重要参考
28 февраля США и Израиль начали военную операцию против Ирана. Ее целью стали объекты командования Корпуса стражей исламской революции, аэродромы, пункты запуска беспилотников и средства противовоздушной обороны.
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