http://www.virtins.com
https://www.circuitsathome.com/mcu/usb/usb-isolator
http://www.boondog.com/tutorials/rfTransmitter/rfTransmitter.htm
http://www.eddiem.com/projects/Pir-remote/pir-remote.htm
http://dangerousprototypes.com/blog/tag/oscilloscope