Abusing Raspberry Pi GPIO pins as a radio transmitter to control my ceiling fan

In Part 1, we covered capturing and decoding the remote control's signal using a USB TV tuner: In Part 2, we take use a Raspberry Pi's GPIO pin as an antenna to transmit our own signals to the ceiling fan. rpitx: The ceiling fan / light combo I have is Minka Aire brand. I think most of the different ones on the market work pretty similarly. ---- Parts: I found my low-pass filter on eBay (overseas shipping). Digikey has low-pass filters that would also work, but not as cheap. eBay low-pass filter: eBay SMA antenna: eBay SMA connector: Note that these all have SMA connectors, not RP-SMA (which look very similar). Also note that eBay listings come and go, so double-check that you get compatible parts. The antenna does not need to be exact - the one I got is listed for 315 MHz and works just fine. ----- Background music: Aerosol Of My Love by Kevin MacLeod Link: inco