RF receptor ramdonly stops working

Hi there,

I'm working on an arduino project that uses 1 RF receptor and 20 RF receivers and for some reason some of the RF receivers do stop working ramdonly every now and then (and not always the same ones), so for example on a normal test, 15 may work and 5 may fail.

I would really appreciate if anybody could point me on the right direction to find out what is causing the problem.

A few facts about the project:

  • The transmitter is working ok since during all the testing at least half of the receivers always do work
  • We are using virtualwire, and the code is not hanging or freezing anywhere since is fairly simple and debugging through serial shows no problem, finally stopping and starting a receiver that is failing does not solve the problem.
  • Every "test" message is transmitted 10 times, so the receiver needs to pick up just 1 of the repeated messages to consider the transmission successful.
  • The are used on an open space (no walls,furniture...etc) at a close range of about 15ish meters
  • all the units use a 17cm wire as antenna which I think is the recommended lenght for a 433mhz 50ohms signal.
  • the transmitter is a c-0503 and the receivers are c-0504, both from Aurel, meant to be quite reliable up to 100 meters.

And that's most of it, any ideas or suggestions will be really welcomed.

Thanks in advance, Javier.