HP50g spins circles around the TI-89

[Manolo Sobrino]

I got my first TI 89 from a folk that had spilled soda on it. I could open it with a screwdriver and clean it: fixed it in 15 minutes and working fine after, a very clean design (see for instance https://www.takeitapart.com/guide/7, but using a pry tool/used card when needed). It took me several try-outs to open a 50g, (non-working, corrupted flash boot issue -the charms of ARM emulation-) and I was getting increasingly angry over the manufacturing quality after every iteration. The last straw was the piece of aluminium coated paper (really? a sheet of cellulose paper under a keyboard?) for RFI shielding and the cheap snap domes fixed to the board with tape... I have my own criteria on dependable tools and the 50g doesn't meet them. Not everything about it is bad though, I like the 50g screen better.

About the software in both units: the 89 is a coherent product with a great pedigree. Its simplicity is intentional, I didn't need to invest months in learning how to use it and I don't usually need to check how to do it. The 50G is a mixed-bag, sometimes it's an amazing device, other times the choices made there look brain-damaged to me. And then it comes with a ludicrous learning curve... When I was younger it looked totally cool to have such complex beasts for the fun of it, now I look first at the expected pay-off before jumping in with both feet. About such calcs for students, I don't think it's a clever idea for them to spend too much time on learning how to use their calculators, they have better things to learn and more urgent things to do.

I'm OK with HP killing the 50g, I can't help considering it a quick and dirt Kinpo hack. But IMO if you're serious about your customers you should give them a migration path for their RPL programs. I don't like being told for more than 20 years that it was the bee's knees and now see how it is discretely dropped. I keep an eye on HP's current offerings but I'm almost out, can't stand many things about the way they work... Too bad they are the only ones offering RPN. It's that or going after hard to repair collectors' items at crazy prices. I guess I'm getting too practical.

Anyway, enjoy your new 50g, yet I'd advise you to not throw away your 89, it can be a comparable time sink if you take the trouble to look for the many goodies available for it, though some are quite obscure now. For instance, Lars Frederiksen's excellent RPN which IMO is the kind of RPN implementation that should have made it to new calculators (yes, it's awful that it doesn't have an inverse key, yet there's little you can do if the TI folks don't put one in the layout) I use it quite often, as well the differential equations package from the same author.