I have bread boarded two Nano modules both have their own NRF24L0 radio. Both boards work perfectly when attached to a computer USB/power port.
Both talk back and forth sending and receiving data. Works great.
However if I pull out the USB/power cable from one board and supply 9 volts to Vin … it won’t transmit or receive anymore. I plug the USB/power/communications cable back in and everything is back to normal. I’ve even used a 120Vac to 5Vdc adapter with a USB output connector and same thing. Won’t Transmit/or receive.
Any ideas?