They were reel to reel.
A friend of mine placed a joke ad in the WA PO, at the time:
“Slightly used 6” reel-to-reel, Model xyz tape recorder for sale. Occasionally skips recording. Call 555-555-5555, ask for Dick”
Thank you for that one, it was a nice way to lighten up my day with the tough times had with the new baby in the house.