Circa 1973
HP-45
Worked great for about 9 years...
Posted on 06/08/2009 6:54:44 PM PDT by mamelukesabre
My HP-48SX ceased functioning about 5 years ago and i still miss it. I recently got the bug to go out and replace it with something. I saw an HP-50 on sale today for about 60 bucks. I bought the 48-SX when they first came out(circa 1989?) for A LOT OF MONEY. I forget the exact amount, but it was either $199.99 or $299.99. I think it was the latter.
The only thing wrong with my 48 is the on/off button. I know this because the problem started out minor and gradually got worse. I used to be able to turn it on and off by pressing extra hard on the button. All the other buttons worked fine. Then little by little it(the on/off button) quit working completely.
I saved the calculator in hopes that I would find a way to fix it. I've tried spraying electrical contact cleaner into the keyboard and nothing works.
I was totally lost without that calculator for a long time after it quit functioning. I had an extra fat wallet for it that doubled as my checkbook. I never went anywhere without it.
This was before I had a cellphone and I'm pretty sure it was before anyone had a PDA. I turned my HP into a primitive PDA. It didn't have a touch screen or internet connection, obviously. But I had files in it with all kinds of personal info and my entire personal phonebook in it. There was lots of old stuff from college in there too.
I was still using payphones extensively back then...along with an answering machine at home that I could call up from a payphone to check my messages.
Since I got a cellphone, the HP became a little less important. I guess that's why I never replaced it. A buddy of mine told me he could program my HP to make the sounds of the phone numbers being dialed so I could hold the calculator up to the receiver of the pay phone and just let it dial like that automatically. He never did get around to doing that for me though...and so I never got to test it to see if it would work. It seems like it shoulda worked though. But I didn't know how to do it myself efficiently without redoing my entire phonebook. I wanted a program that would take a pre-existing stored number and convert it into the sounds required to dial a number. That was a little over my head.
Even to this day, sometimes when I pick up a simple handheld calculator and start punching in numbers real fast I accidentally revert back to RPN and have to start all over. IT REALLY SUCKS! And it's been 5 years since I've ever touched anything that uses RPN!
Can’t help you but I do remember reverse polish notation!
In college I used my HP allot for Statistics.
My HP-25 got me through Calculus in 1976-1978.
I still have my HP 12C business calculator.
Consider buying an iPhone instead, which will not only do RPN in a calc app, it will link to your computer so you will never lose your information if the on-off switch dies.
As for the rest, my iPhone tells me that you can find HP48 repair information at http://www.hpcalc.org/hp48/docs/opening/
My 48GX is slowly dying.
You might resurrect yours for awhile by pressing below the screen in the middle of the row. I am not kidding.
Then the ON/OFF button will work.
There is a short in your calculator.
Soon the functions along the right side will start failing.
It is kind of like watching an old friend die of cancer.... Not really but it sure sucks to have your calculator die. RPN with multiple stacks is the only way to go.
I still own my father’s 2 HP-45’s, both still functioning!!!!
I also own an HP-41CX, and I have 2 HP-48’s as well!
Tear the button off of the offending switch.
The keypad is a bunch of switches.
Figure a way to conduct electricity through that switch.
It may take a simple press of the underlying bubble switch or a metal contact (jewelers screwdriver) to let the electrons flow from the pull to the throw of the switch.
HP still makes RPN calculators. I had one that carried me thru college all the way to a BSEE. I don’t recall the model #. I have an HP 12C that I bought in about 1985, and I believe it is still running on the original batteries. They still make the 12C, and it still costs $70.00.
If you buy an iPhone, there are many apps that effectively mimic the HP-48 almost perfectly. They range between $4-$14 I think
That was a premium calculator! I had one around then that did basic +/-/*// functions and reciprocals...it cost $90.
I will try that. And yes, that is very sad. I’m almost thinking about waiting to resurrect my HP until later so I can have my old friend awhile longer.
True to its name an RPN calculator requires you to start with the answer and work backwards.
Think ‘Jeopardy’.
:)
Had one, hated it.
I paid $289 (one month’s rent) for my 48SX in 1991. It doesn’t get used daily any more, just special occasions.
I used an HP-48C in College, early 1980's. I still have it, but it is kind of bulky to travel with.
Recently I bought the only RPN calculator allowed for the PE exam. It's cheaply made compared to the original HP calcs.
But I can't stand not doing RPN. Parentheses are the pits.
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