Free calculators, what to do with them?


I recently was given many HP items for free (!) by my very nice math teacher at my college. Here's what I was given:

1. HP 82240B printer (has a roll of thermal paper, it works fine, no wall wart cable with it, though)

2. HP 48GX (no expansion cards, works great otherwise)

3. 4-pin serial cable for the 48GX, haven't tested it yet

4. Various books for/about HP calculators (mostly manuals)

5. HP 28S, looks like it's brand new (it still has that "new" smell, after 22 years of sitting around, unused... amazing)

Most of the items have markings indicating they were the college's (permanent ink + etchings), so no chance I'll be selling any of these. My main question is do you think it's worth paying $40+ USD for these rechargeable N-cells and corresponding N-cell charger for use with my 28S:

This is just about the only place I've found that has rechargeable N-cells AND a charger for them (there's other stores with the mimio products, but they're the same price as the mimio store). I'm just wondering if it's worth getting those batteries/charger because I do currently own an HP 50g, and it works fine for me, but would a working 28S be worth using, for reasons beyond it's better battery life?

Oh, if any of you have bought those batteries/charger and happened to find they work for your HP that takes N-cells, I'd also like to know if those work, before I decide to go buy them and find they don't work in non-mimio devices...


Lucky you!

Just buy some non-rechargeable n-cells at a shop like Future Shop or Radio Shack or Walmart or something like that. Might run you something like $10-, but how often are you going to use the 28S after all. Also, non-rechargeables last longer and I strongly advise minimizing taking in and out batteries from those stupid clamshell models.


I strongly advise minimizing taking in and out batteries from those stupid clamshell models.

Excellent advice! The battery doors are the weakest part of the whole design. I wouldn't recommend even keeping the batteries installed, since that puts pressure on the door and the case has a tendency to fracture around the door. Both my HP-28C and S model cases broke near the door after a long period of storage, with the batteries installed.

Fortunately, the HP-28 series is one of the least desired of all old HP calcs, so they show up often and cheap on eBay!



Even if the 28S might be cheap (in every respect) I like it very much. The dedicated alpha keyboard makes a lot of sense when you are programming in RPL. I like it more then nested menus or catalogs.

The 28 series is the RPL anchestor and, as such, very interesting. The later models are overloaded und their dialog boxes and menu systems distract from programming. On a 28, the angle brackets make more sense then on any other RPL model.

Use it!


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