N_Cook wrote:

On 13/12/2017 08:33, N_Cook wrote:
Like timing chains and toothed belts but for transfering positional info
rather than motive force plus timing.
So like the sprocket holes of Cine film or in this case more like the
central line of perforations in paper baudot tape. In this case thin
steel tape with central line of perforations, that engage with pulleys
with balls half set into drilled holes in the periphery of the pulleys,
same spacing, to engage with the holes ?
At first, I thought you were looking for "Geneva mechanism". But, if you
are looking for the belt/chain drive, then the term would be something like
"timing belt" or "sprocket drive/belt".

Jon