Robin2:
You need to be careful here. You can't actually tell whether the problem is with the Tx or the Rx.
...R
Well, I've done quite extensive testing with a lot of combinations and everything seems to suggest that the issue is with sending. I'm trying the basic example that would send a value, and if it receives a valid response, it will add 1 to the variable and send it again, so you can figure out if the whole communication is going in both ways:
nrf24l01 <-> nrf24l01
This scenario works just fine... one side sends, the other receives, responds, and the loop goes on fine
nrf24l01 <-> nrf24l01-pa-lna
one side sends, the pa-lna receives, but fails to send anything back
nrf24l01-pa-lna <-> nrf24l01
Nothing happens, there is no initial packet being sent
nrf24l01-pa-lna <-> nrf24l01-pa-lna
Nothing happens, there is no initial packet being sent
Finally, when trying a "scanner" example from the library, all modules would pick up noise on some channels...
To me, it is pretty clear that there is an issue with sending from the nrf24l01-pa-lna modules...
I have found this guy, experiencing the exact same thing, with a rpi, not arduino, but still... NRF24L01+PA+LNA msg send failure | MySensors Forum
Now, it may be a power issue... but I am unable to figure it out...