On Mon, 28 May 2018 11:46:37 +0100, Graeme wrote:

In the meantime, if I leave the PC on, will the internal battery charge,
or is it not rechargeable? PC has probably not been booted for 20
years.

Its probably beyond its life so try sticking a new battery in. AIr Elonex
were easy ones to get into and play with.