Re: HP-33C repair


I will try to get the NiCd batteries tonight at my local Radio Shack. Still, I don't know if the fact that calc's current battery pack is dead was the cause for the display of the calc to go haywire. As I mentioned before, there's no response to key presses except that, sometimes, the display will go blank after too many key presses. The keys, though, still have the clicky feedback you get from the old models of HP's and the calc looks brand new.

I very much appreciate your responses to my queries and will keep you posted on any developments with my brand new HP-33C.

(BTW, I just bought a brand-new, in the box, HP-42S, complete. The serial number starts with ID027, which indicates that this unit was manufactured in the 27th week of Y2K. The manual, still shrink-wrapped, ia a little yellowish, and is dated 1/92. Sometimes it pays to venture into these vulture-like electronics stores that take advantage of tourists. I only paid $59.95 -$64.93 with the NY State sales tax- and I'm thrilled by the deal, after seeing these go for close to $200 at eBay.)


Radio Shack has rechargeable replacement AA cells that are Catalog Number 23-191 rated at 1.25 volts. Although it is tempting to use any AA cell particularly of a higher rating I believe you're always on the safe side of the calculator's power requirement if you used the specified 1.25-volt for it. And always use its charger only with its battery pack installed. Once the calculator lights up you can try pressing STO ENTER and if the circuits are alright it should display an -8,8,8,8,8,8,8,8,8,8,. Actually any electronics retailer has a battery for the HP-33C. I have an HP-33E which is similar to the 33C and I use 1.2-volt rechargeables in it.


A few years ago I bought a 33C at a tag sale (for a buck) which also didn't work. I don't remember exactly how it was put together inside, but as I recall various parts were plugged or pressed together in a way that made contact iffy, and when I took it apart and put it back together it was fine.


Hi, folks:
Following everybody's advice, I went to Radio Shack to check on their rechargeable AA battery packs. Unfortunately, in a couple of stores I visited over the weekend, they were out of cat # 23-191. They had, however, another pack cat. # 23-260, rated at 1.25V too. This pack, however, cost almost as much as I'd paid for my HP-33C. Being the cheapskates I am, I decided to buy some Panasonic rechargeables (only $4.99 a pair) and used a small metallic piece to join them at the bottom (I decided not to disassemble the battery pack). After charging them, my HP-33C is now working beautifully. It passes the self-check test (thanks Romeo) and keeps programs stored and register contents after turned off. It's a beautiful machine. There's such a great feedback after pressing the keys you feel like ditching your state- of-the-art HP-49G.

Anyway, thanks everybody. My HP-33C is now the oldest calculator in my collection (serial number starts with 2241), but it works flawlessly even after a lot of abuse it must have been put through at the shop where I bought it. The salesman didn't even have the battery pack installed in it when he plugged it to the AC outlet to show me it was working. It shows how resilient these old HP calculators are.


Mr. J. Lopez:

You're welcome. It's a pleasure to be of help.




Real cheapskates buy discontinued cordless phone battery packs in Walmarts, etc. for $.50, sometimes with up to 6 AA cells, already jumpered and then cut them apart!! ;+} If not, Qty 10 of the 5 cell packs can usually be bought from a distributor for about $2/ea.


Wow! Now you tell me! Gotta start going to Walmart's more often.

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