the stations won't receive what i transmit

[iw9hlv]

Ciao, i've tried your arduino skecth as transmitter, i heard the various type of RF emitions, one by one but my tree oregon stations won't receive nothing.
As receiver all work properly but as transmitter don't.
My tx board is an STX882 and is perfectly centered at 433.920 Mhz.
What is wrong ?
I'm stuck on this ...