Under the little flap where the notepad goes?
Yes – this is where it is. A bit awkward but folds down from the top.
EDIT: Folds from right to left – see photo attached to Beozips post here: https://archivedforum2.beoworld.org/forums/p/42465/309140.aspx#309140
EDIT 2: From Beocom 1401 manual:
Location: Warwickshire, UK
My B&O Icons:
