GGunn,
So, you have been around that long!
Thanks for sifting the memories.
I used a slide rule the first time around.
After that (two more times) I used the TI-59.
In the Ti-PPX, we poked a lot of fun at the HP line.
Fine instruments and RPN was OK, just like loading PDP-7 registers.
RPN was bullet proof!
Our best poke was that the 41C first came out with 2^2 = 4 and SQR(4) = 1.999...
None of could figure how that got out of the design shop!
Of course, HP fixed it after the first shipment was out.
I still have all my old TI papers, calculators, and PPX newsletters,
but like many of use, life has traveled on further, and further.