Collecting Hewlett-Packard Calculators

Selling Hewlett-Packard Calculators


18th May 2003

So you have a Hewlett-Packard calculator left over after college days and you want to sell it. Where do you sell it?

Obviously, you sell it on eBay - the largest world-wide bazaar for turning your old junk into someone else's prized possession, and earning a nice chunk of cash for yourself.

But how do you sell it on eBay? Go to and check out the selling guides. You'll have to sign up, go through the verification steps, and get yourself established. If you already have good feedback on eBay, then you are in the best possible position. If you have zero feedback or feedback less than 10, then you have a small problem. Bidders will be reluctant to bid because of your newness. So do some buying. Buy a few small items. Sell a few small things. Get yourself 100% good feedback over 10, and then you are ready to start selling your HP calculators.

Anyone can sell their calculator, but not everyone gets a good price, let alone a great price. So how do you get a great price for your calculator on eBay?

You have to do research. If you want to get the best possible price for your calculator, you have to do some work.

  • Put the model number in the auction title. How can people bid on your auction if they can't find it? Look at the best titles of existing auctions, and do likewise.
  • Learn how to describe your calculator. Search on "HP calculator" and look at the auctions. Search on your specific models and see how they are described. Be honest in your description. If your calculator has flaws, describe them. Best to be honest now than earn bad feedback, charges of fraud, and get hounded by irate buyers. The better and more detailed your description, the better your price will be.
  • Learn how to display your calculator. Look at the other auctions and see the photos that are used. Don't use other people's photos. Take your own photos of your actual calculator. Several photos are best - good clean, clear close-ups showing the front and the back, and definitely showing the calculator working. Best of all, include a photo showing the results of the self-tests. See the HP Calculator Museum for how to run the self-tests. The better the photos, the better the price.
  • Use a low starting bid. Do not have a high starting bid or no-one will start bidding. A low bid encourages people to start bidding. Once people start bidding, the psychological aspects of ownership encourage continued bidding.
  • Don't worry if you get no bids in the first few days, or only one or two bids up to the last day of the auction. You'll get a lot more bids in the last minute of the auction. It's also great if you get a new bidder, because they don't have a clue on how to bid and try and win the auction through the entire auction. The wise bidder knows that the only time you want to be winning the auction is when it ends. Hence the flurry of bids in the last minute.
  • If you are confident that you have a great calculator that will sell well, then don't bother to set a reserve. But if you are scared of selling your calculator too cheaply, or it's your first auction and you're worried that your lack of feedback will hinder your chances, set a reserve price. A low starting bid encourages bidding, and a reserve guarantees that you won't have to sell it too cheaply.
  • But how much should the reserve be? Do some research. Search eBay for completed auctions for your model. Note the closing prices. Note the condition and the extras it came with. Estimate what yours will be worth. You'll always over-estimate, because you want to. Try and be realistic. It costs you money if your reserve is too high and the calculator doesn't sell. You still have to pay eBay. So be realistic.
  • The final selling price (and your reserve) depends on many things. If the calculator doesn't work, it will still sell, but not for very much. If it works, you get a lot more money. If it can pass the HP self-tests and you have a photo showing the self-test results, you get more money. If the items are unscratched and undented, and the photos show it, you get more money. If you have the original case, you get more money. If you have the manuals, you get more money. If you have add-ons, you get more money. If you have original boxes, you get a lot more money. The better the condition, the more money you get. The better your description, the more money you get. The better your photos, the more money you get.
  • Some models raise more money than others. The HP10C, HP15C and HP16C generally sell well. The HP41C sells well, as do the HP67 and HP97. Older models sell well. There are rare ones, and special editions. You have to do some research to see what yours is worth. There are a lot of resources to help you determine what yours is. Use the links elsewhere on this page, and do some research.
  • Alternatively, if you don't want to do any work or research, sell them to me. I'll offer you $10 to $40 for your calculator depending on what it is. Probably a tenth of its value. And I'll want to do escrow or something else like that, and I'll want you to pay for it. I'm usually reluctant to buy outside eBay. With an eBay auction, you can use feedback to help judge the integrity of the seller. You have comebacks if the seller or the buyer tries to cheat you. You have less safety if you sell outside eBay. But I'm willing to take the risk if you're willing to sell your calculator at a tenth of its value. But you'd be a real chump to do that. Best if you do your research, and do some homework, and sell it through eBay and get a decent price for it.
  • Be honest. Don't cheat. Play nice.
  • Good luck.

Buying Hewlett-Packard Calculators


26th April 2003

I've been asked quite a few times where you can buy Hewlett Packard calculators today. It's been a few years since I saw any in the stores. Last one I saw was a HP12C in WalMart, but that was in 2001. Before then I saw a few of the cheap ones in a Best Buy, but they didn't stay available for long. Since then, I haven't seen any new calculators in the stores. Texas Instruments have won. Their calculators are faster, cheaper, and they're ubiquitous. And they don't do RPN so the masses can understand them. And they have no soul. So of course they're everywhere.

If you're looking to buy Hewlett Packard calculators, you have a very few limited places to look.

  • Pawn Shops. However you'll usually get them without any manuals. You'll need the manuals. Some of the manuals are available from the HP Calculator Museum CD disc set. The manuals for newer calculators won't be available there. You'll need to wait patiently for the manuals to turn up on eBay. And eventually, they will. Today, pawn shop owners price their calculators through watching eBay auctions. It's rare to find a bargain, but they do turn up occasionally. Be wary, and test the calculator thoroughly. Look out for scratched screens, battery compartment corrosion, and damaged keys. Test it thoroughly before you buy it.
  • Ask your relatives if they have any HP calculators lying around the attic. If they've been to college, you might be surprised just what they do have tucked away. Offer them $10 for the calculator and you might be pleasantly surprised. Ask parents of friends if they have any. Ask anyone in their 40s and 50s if they have HP calculators lying around and if they want to sell them.
  • The HP Calculator Museum classified ads. Have a look on the site, find the classifieds and see if they have what you need. Also check out the notes on where to find HP calculators that's on the museum. They have some good hints there.
  • Samson's Cables online store. These guys specialise in HP calculators and accessories. I've bought from them and the experience was very pleasant.
  • Asena's Shop. Go down to the site directory and look under electronics, and click on Calculators. They usually have some Hewlett Packard calculators available. I've also bought from these guys, and again, it was a pleasant experience.
  • eBay. eBay always has HP calculators for auction. Hundreds and hundreds of HP calculator auctions every day. Just search on "HP calculator" and spend an hour or two browsing through what's available. And yes, I've bought HP calculators on eBay, and I've never had a bad experience.

New Calculators - HP 9S and 9G


5th March 2003

Hewlett Packard have released two new calculators. There's the 9S which is a small cheap limited scientific calculator, costs about $12. And the 9G is a small cheap graphing style calculator, costs about $50. They both have the same size and shape, similar to the earlier 30S. And they're both algebraic calculators.

With the addition of these two calculators, I have run out of my space in my display cabinet. I'll have to get a second one, as I have a few more older calculators on the way.

[HP 9S and HP 9G

Storage Unit for the Collection


21st July 2002

I finally found something nice to store the calculators in. This is allegedly a toolbox. I've never seen a toolbox lined with felt and made from such nice wood. It's more like a jewelry box, only bigger.

HP Calculator Display Box

Why I Started Collecting Hewlett-Packard Calculators


22nd June 2002

In 1999, I wrote a few words about my early history with Hewlett-Packard calculators.

I started with HP calculators way back in the early 1970s when I was at university, when I bought a HP45. Then came a HP25, and then a HP67. Those machines came and went. Some died, and one I sold. Later in the early 1980s, I bought a HP11C. I still have it. In the late 1980s, I happened to be passing through Singapore and found a HP16C, the programmer's calculator. I still have this calculator, and still use it at work. Those two calculators served me well till 2002, when I found a HP48GX in a pawn shop, and that started the collecting habit.

So I started collecting HP calculators. I didn't want the older machines that require the special battery packs, and had the red LED displays. I was nostalgic for them, but they cost a lot of money and are hard to keep running. I was more interested in the later breeds of HP calculators from the 1980s onwards, that used replaceable batteries and had LCDs. And even though I love RPN, I was curious about the breed of algebraic calculators that HP produced.

My collection begins with the flat brick models of the early 1980s, ignores the last of the HP41 models, and continues with all the calculators produced since. The advantage of this is that they are fairly inexpensive to acquire.

HP Calculator Links


To help me in my quest for information about the HP calculators, I found a number of really excellent web sites. I didn't find much information on the HP site. They only appear to list their current calculators.

My Collection


Model Year Type Entry Method Cost Notes Have? Photo
6S 1999- science alg $10 Thin and small, body has blue tint which makes it hard to see the secondary functions. Uses batteries. Yes
6S Solar 1999- science alg $10 Thin and small, solar powered. Turns on when you pull it out of the case. Body has a silver colour, so all the key functions can be clearly seen. Yes
9S 2003- science alg $12 Thin style, with sliding cover, similar in shape and size to the 30S. Removable faceplate, mine was white which makes it very easy to see the second functions. Where the 9G has a gold cursor button, the 9S has a big button same size in silver with the HP logo on it, but it doesn't move and it does nothing. Decoration. This is a simple scientific calculator. It's got the standard sets of maths functions, statsistics, and base calculations. A little formatting allowed. Only a one-line display. It's not programmable. Uses two LR44 batteries. Yes
9G 2003- graphing alg $50 Thin style, with sliding cover, similar in shape and style to the 30S. The big arrow key is gold coloured with the HP logo in it. Does graphing, is programmable, and does HP Basic. Removable faceplate, but no extra faceplates supplied. Uses two LR44 batteries. Comes with a few pieces of paper for the instruction manual. No decent instruction manual at all, but for $50 what do you expect. Graphing is coarse, and the screen is small, but it does the job. Yes
10B 1989-2000 business alg $50 small financial calculator Yes
10BII 2000- business alg $30 rubberised sides Yes
10C 1982-1984 science rpn $80 simple scientific calculator
11C 1981-1989 science rpn $135 scientific calculator Yes
12C 1981- business rpn $150 the ultimate financial calculator Yes
14B 1988- business alg business and statistics
15C 1982-1989 science rpn $135 scientific calculator that also does matrices
16C 1982-1989 programming rpn $150 programmers calculator Yes
17B 1988-1990 business alg $110 simplistic keyboard, menus
17BII 1990- business rpn/alg $110
18C 1986-1988 business alg $175 folding business calculator, alpha keyboard on left, menus buttons with changing menus Yes
19B 1988-1990 business alg $175 folding case
19BII 1990- business rpn/alg $175 last clamshell folding model
20S 1989- science alg $50 solid scientific calculator, programmable Yes
21S 1989-1993 science alg $50 programmable
22S 1988-1991 business alg $60 science and stats, menus and a solver
27S 1988-1991 science alg $110 scientific, but had stats and financials, but no programming memory
28C 1987-1988 science alg $235 clamshell folding style, symbolic maths, alpha keyboard, 2K memory Yes
28S 1988-1992 science alg $235 programmable, graphics objects, directories, symbolic maths
30S 1999- science exp $15 programmable, replaceable colour keyboard layers Yes
32S 1988-1991 scientific rpn $70 science and stats, complex numbers, menus and a solver, programmable
32SII 1991- scientific rpn/alg $70 Programmable Yes
38G 1995- graphing alg $120 Weird sliding cover, 32K, applets Yes
39G 2000- graphing alg $70 Tinted see-through removable hard cover, 256K, applets. New style keys, small and ugly. Yes
40G 2000- graphing alg European model
42S 1988-1995 scientific rpn $120 science and stats, complex numbers, menus, built-in functions, programmable, complex numbers and matrix
48S 1991-1993 graphing rpn $250 32K RAM, not expandable. Has a brown colour scheme, pleasant looking. Yes
48SX 1990- graphing rpn $350 32K, expansion slots, has the pleasant brown colour scheme. Seems to be the same as the 48S, but it has the expansion slots. Yes
48G 1993-1999 graphing rpn $165 32K RAM, not expandable. all operations are the same as the HP48GX. Has the blue/green colour scheme. Yes
48G+ 1998- graphing rpn $180 Australian model
48GX 1993- graphing rpn $350 128K RAM, has 2 expansion slots, one for a RAM card and one for an application card. Yes
49G 1999- graphing alg/rpn $180 1.5 meg RAM, new sleek body style with coloured case. Keys are not the same much-loved HP style keys, but ugly small buttons. Does both algebraic and RPN, but the Enter key is at bottom right, which is clumsy. Screen resolution appears better than the 48 series. Yes