I learned 1A2 in the early 80's. I had just mastered the diode matrix when the Tie Econokey came out. It was a small blue box and you entered a bunch of 0's and 1's in programming. So much for all my training.

Ah for the good old days when the only questions you had to ask a customer was: what phones do you want to ring and what should we set the hold recall for.