So I too got my hands on one of those cheap 433Mhz transmitter/receiver components. I've followed nearly every tutorial about connecting them to a Raspberry Pi but I can't seem to figure out the following:
The tutorials state that I should hook up the VCC of the receiver to the 5v pin. This however makes the unit unable to receive any signals using RFSniffer. When I connect the VCC pin to 3.3v, I get signals but only from a few feet away.
What am I doing wrong here?
If the datasheet of the 433tx/rx says 5V and you connect to Raspi at 3.3V pins, you'll need a levelshifter
see:
or: //cdn-shop.adafruit.com/datasheets/an97055.pdf
for rx it could be enough to try a resistor with about 220 Ohms in series, but I recommend the levelshifter with one FET.
The receiver should be powered with 3V3 for best reception. The transmitter can do well up to at least 9V. Remove the coil if you add another antenna, and remember that l = 300/f, and f = 300/l .
