In message , at 21:24:43 on Tue, 15 Oct
2019, tim... remarked:

How did one pay for the journey in 1981

almost certainly cash

Coins.

and what cind of ticket did
you get? Magnetic stripe?

Unfortunately my collection doesn't go back that far

but definitely mag stripe

Yes. Introduced for the Victoria Line I think.

the question is would that have been a credit card sized ticket or did
they still have Edmondson sized "Yellow" tickets then?

They were yellow, but somewhat bigger footprint (and none of the
technology of) Edmondson.
--
Roland Perry