[craigruaux]

Hi craigruaux,

Everything is right in both Config_Options.h files.
As you suggested, I also agree that the problem most probably is caused by a faulty TX or RX module. Without additional equipment (like an SDR pen) isn't easy to know which one is. The easier way is to replace both the TX and RX modules.
Have you checked if both TX and RX modules are 433Mhz versions? I know that it sounds stupid but sometimes happen that we order from sellers which sell 315MHz and 433Mhz versions and we or the seller swap the version.
Can you post some pictures of both modules?

I'm comfortable that they are both 433 Mhz modules, by virtue of the fact that they both have 433 printed on their resonators.  Getting them off is going to be a bit of a chore, I'm now regretting that they are not in sockets .

I have a spare receiver module, I might put together a simple receiver to see if I can hear anything. If I a correct the data is in a 20 character string, right?

I also have one of the wireless display units, and I know they can receive via RF. Would they, in default configuration, receive from a TX unit in basically default configuration? Or do they rely on the relay transmission from the RX unit?  I have tried with the wireless display, but have not seen anything from it.