Hi Ron,
I had a look at that schematic you posted, and yes it is similar
to what i have in mind.
I was intending to use the type of relay that has a pair of C/O
(change-over) contacts, this is probably the most common contact
set found on small relays.
I had in mind to use one set to operate a transistor, and the other
set to be available for external use, isolated.
My mind keeps going round and round the ways of connecting the
transistor to the changeover set, and the ways of using the input
pulse ....
but i haven't done it yet.
I have convinced myself that it can be done with just a few
components (but i may be wrong ... )
If you happen to glimpse a possible way, please post it anyhow,
even if it is absurd, cos it might help me to think of a way.
Regards, John