I seem to remember the HP67.
We were the last Adv Tech Course to get PO'd on the Arty Slide Rule, and then toss it in the garbage !
Because we had learned to compute all survey functions with a pencil and log tables ( as well as with a CP&FC Graph, or Table C in the Firing Tables ), we too thought we had died and gone to heaven !
The pocket calculators came in as an interim measure, a stop-gap, if you will. MiliPAC was in the developmental stages and was still a few years off. My Adv Tech Course was the first to do a live-fire practice with other than an Arty Booard or Plotter.
I went back to the School six years later. My AIG course was the first to fire live with the MiliPAC !! Man, those days were scary ! The Illum program would give you a parallelogram instead of a diamond illum !! To quote Ray Melanson ( a noted AIG and, later, Master Gunner, " you would have to fire a round at every mil of bearing and elevation to prove this thing ! "
Ubique