"N_Cook" wrote in message
...
Is the isolated switch just for the situation of switching on an inbuilt
guitar amplifier or is it somehow wired in to cut plug-in bangs through an
amplifier. I don't see how the latter as first contact would be the tip of
the guitar lead will hit the ground/shell of the socket , and so act as
stray pickup, before anything else is electrically connected




It is to switch the negative side of the battery supply to either an active
onboard preamp, active pickups, or both.


Gareth.