Test circuit to confirm RF receiver frequency? (315Mhz vs 433Mhz)
Realistic Performance Expectations

Many of the cheapest RF modules are sold with very unrealistic claims of data rate and maximum communication distance, and sometimes with very little (or even incorrect) documentation. VirtualWire will help these modules perform as well as they can, but the old saying applies: "you get what you pay for".
For example, the 315 MHz modules shown above were documented with only this image.


Source: // https://www.pjrc.com/teensy/td_libs_VirtualWire.html