I recently did some work on a Japanese 360* tracked-excavator .
the boom could be shifted from it's central-position...control was a mechanically- latching relay- in essence, like a domestic pull-cord light-switch.
short pulse to change-over contacts..another short pulse to revert to previous state..... IIRC the relay was made in some Eastern-Bloc country, not noted for it's high-tech industries.
@ mickjoebill..... they claim they haven't the room ,or the weight- penalty is too high to add a third battery/ increase the capacity of the current two fitments /change to a more stable technology......
But they can find capacity for a glorifird Victorian steam-boiler!!
