[David Simpson]

Thanks guys for all the info. As Andy says, it would be athsetically preferably to keep the original pulsed mechanism, I was merely guessing that a quartz mechanism was the only option these days. The "Piexx" conversion looks the bee's knees, but guess its hellish expensive sourcing from the USA. Wonder if there is a UK supplier of a similar kit ?
The existing mechanism doesn't look too grubby or worn, and a gentle tap on the solenoid arm clicks the minute cog one tooth past the pawl. But hey - I ken sfa about these things, but hope to learn.
Mark - yep that wee switch contact had me puzzled - I'll try & take a decent macro picture of it.
How are the hands secured to their spigots ? By wee knurled nuts or a tapered press-fit, or what ? The securing nut for the whole mechanism is a bit loose beneath them. I wont attempt any removal until "I'm telt fit ta de".
Having banged-on in the past about inexperienced folk poking about inside AVO VCM's - here's me delving into heffing big clocks, eh !
Mind you, I used to service & repair Sangamo Weston time clocks years ago, but I'm treading very carefully with this big thing.

Regards, David