Wake up Faded Display on HP 32S Calculator?

Art Duino

Joined Nov 30, 2017
30
I have an old HP 32S calculator. I used it so much in college and grad school, I got very used to it. The display has faded, however, so using it is very unpleasant. There is little contrast now.

I got myself a new 35S, and HP welshed on their written promise to send me a paper manual, so now when I want to learn how to do something, I have to look at a ridiculous PDF, or I have to print the 352-page PDF out and keep a fat, clumsy bundle of papers next to me.

I would love to put the 35S in a drawer and use the old 32S. Is there any way to get a faded calculator display to work better?

dl324

Joined Mar 30, 2015
12,451
Have you tried changing the batteries?

If the 35S is too difficult to learn, look for a used 32S.

Art Duino

Joined Nov 30, 2017
30
Indeed, I did remember to replace the batteries.

The cost for printing and binding a 35S manual is about $46. I'm amazed that Hewlett-Packard promises a paper manual and then weasels out. dl324 Joined Mar 30, 2015 12,451 Indeed, I did remember to replace the batteries. Then you're probably out of luck. Look for a used one. The cost for printing and binding a 35S manual is about$46. I'm amazed that Hewlett-Packard promises a paper manual and then weasels out.
If you print 4 up, duplex, that's only 44 pages.

Art Duino

Joined Nov 30, 2017
30
I may dump the 35S and spend \$19 on a new TI 36X Pro, which comes with a free 78-page paper manual. I was hoping to stay in the HP family for sentimental as well as practical reasons, but I think HP is not serious about calculators now. They only sell 3 non-graphing scientific calculators now, and their website and customer service are crap.

wayneh

Joined Sep 9, 2010
16,790
Indeed, I did remember to replace the batteries.
I’m still suspicious of the power. Maybe a corroded spring or contact, or the “new” batteries weren’t fresh. My HP calculator screen always faded as the batteries were failing.

Art Duino

Joined Nov 30, 2017
30
I can try scraping the battery contacts.

wayneh

Joined Sep 9, 2010
16,790
I can try scraping the battery contacts.
Do you have a multimeter to measure voltage? Just one dead cell or a poor connection is enough to cause this.

crutschow

Joined Mar 14, 2008
26,376
Would you consider a virtual calculator?
Here is a virtual HP-42S calculator that can be installed on a PC or a smartphone, that looks and works identically to the physical calculator.
The graphics are remarkable, as it looks just like the real calculator, even the display.

I'm a big fan of HP calculators and RPN, so this was a great replacement for my old HP-42S, whose keys sadly started failing.

Art Duino

Joined Nov 30, 2017
30
I believe I have that app on my phone. If not, I have another one like it.

I wish I had known LCD displays were mortal when I let myself fall in love with the 32S.

I do have a multimeter. I haven't found the courage to open the 32S up, but I guess I might as well.

dl324

Joined Mar 30, 2015
12,451
I wish I had known LCD displays were mortal when I let myself fall in love with the 32S.
Few things last forever. My HP41C stopped working 30 years ago and every so often, I think about getting a replacement. The serial number was under 100; it was supposed to be a life test unit, but I knew someone. The alternative was a 6-12 month wait (I got it when it first came out).

Mine likely stopped working because it got wet.

Art Duino

Joined Nov 30, 2017
30
I still remember the days when HP bragged about how tough their calculators were. "Back your car over it! No problem!"

Just don't put it in a drawer in a cool, dry room for 15 years. They didn't warn me about that.

dl324

Joined Mar 30, 2015
12,451
I still remember the days when HP bragged about how tough their calculators were.
The company changed and is now just a shadow of its former self. When I worked at HP, HP stood for Have Pride.

Art Duino

Joined Nov 30, 2017
30
I picked up a TI today. I'll see if I can find happiness with it, and if I can't, I'll screw around with the HP until I get it fixed or destroy it completely.

crutschow

Joined Mar 14, 2008
26,376
I picked up a TI today. I'll see if I can find happiness with it
Good luck with that.
I know I couldn't with a calculator that doesn't use RPN.

Here's a screenshot of the virtual HP-42S on my PC:
One really neat feature on that calculator is the Solve function, which will solve for any unknown variable in an equation after entering values for the other known variables.
For example if you enter the equation of F = 1/(2PI*RC) into the program memory and then enter values for F and R, it will solve for the value of C
[Shown below for an entered value of 10kΩ for R and 10kHz for F, and then pressing "C"(1/X).]

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