Most Just Add Power devices will not allow an incompatible firmware to be loaded onto them. Unfortunately, the 705POE and 715POE are close enough that their firmware files can be loaded on each other.
If you find yourself in the unfortunate position of loading the 2GΩ/3G+ Transmitter firmware onto a 2GΩ/3G Transmitter, the 2GΩ/3G Transmitter will be unable to accept video signal from any source.
To return the 2GΩ/3G Transmitter to a functional state, apply this command through a telnet session to the Transmitter
astparam w v_type;astparam w v_loopback_type 1;astparam w v_rx_drv;astparam save ro;reboot