Harry -

yes the control unit uses a separate supply which as Rob says you can "T" off the ECU battery. I have only tried them in the way the manufacturer recommends so not sure what happens if you use a regulated 5 or 6V from the rx. Im guessing at the very least they will not have as much "lifting power".

This is where the LADO units score as there is no separate box or battery supply required - just plug straight in to the RX - ideally at 6V regulated.

We have both the LADO and Electron (although we only have the ER-40's at the moment - and trunions to accept 6mm pins)

regards

Colin