I have 1 Uno R3 and would like to test 433 MHz transmitter and receiver through one board, using 2N222 transistor as a switch. From what I've read, transistor emitter to ground, base takes resistor (I'm using 720 ohms) to digital input on Uno, and collector interfaces with transmitter...vcc? I'm not sure how to connect all this together with transistor.
I also have 555 timer IC's; are they a better option? Explanation or links to diagram of 2N222 or 555 timer linking to any sensor's vcc/ground/data, and the board, would be appreciated.