Ah, the joys of sending new L Mech ADs off to stores for a new set of range rings for the radar....
In the days that LACs had to pass TAT (Trade Ability Test) 1 and 2, we managed to convince one keen young chap that a MENSA application quiz was the newly-introduced TAT 3. After an hour he emerged from the radar cabin we'd sent him off to sit the test in having made a not half bad go of it!