433Mhz RF link kit - not receiving...


I bought this kit and using VirtualWire had it working perfectly (although range was a bit of a problem). Then suddenly it stopped working. Even using SoftwareSerial, I used to get lots of noise coming through… now there’s nothing.

Is there a way to check whether the receiver is working correctly? I tried another receiver (I bought 2 kits) and same problem.


Hi, :slight_smile:
What is the mean that it suddenly stopped , and you got lots of noise coming through? Before check if the receiver,make sure that the way you used this RF link kit is right.

Demo code:
Hardware connection:
you need to used two arduino board.
Receiver D11 on one arduino board
Transmitter D12 on another arduino board


Hi Deray


Sorry, let me explain more clearly:

  • I connected 2 Arduino’s to 2 serial ports on my computer so I could monitor them. The receiver was on the one board and the transmitter on the other
  • I first used SoftwareSerial library to try to communicate - there was lots of noise coming through on the receiver - a stream of numbers that had no pattern
  • I then use VirtualWire, and it worked perfectly - the message went from transmitter to receiver.
  • After some time - maybe a 5-10 minutes, the receiver was only picking up the data from the transmitter sometimes. I tried using wire for an antenna, and also making sure the transmitter was on 5V.
  • Then a short while later, I was receiving nothing
  • I did not change any wiring during this time.

So I thought there could be 3 problems:

  • Arduino

  • Receiver

  • Transmitter

  • I tested the Arduino port with another sketch and it worked ok.

  • I can’t test the transmitter, because it needs a receiver to test it :wink:

  • I then thought maybe I can test the receiver using SoftwareSerial, and check whether it is still receiving lots of noise. The receiver was receiving nothing…

I can’t think how it could just stop working. I tried the same with my second receiver, and the same thing happened. After that, I tried the first receiver again (maybe it overheated and was now cool again). It was just quiet, didn’t seem to be receiving anything.

Thanks for your ideas and help.


USB Power source are very bad. Try powering by battery.
Small distance between rx and tx are not good.
Small distance to PC is not good (they are like a hf jammer).