HP42 calculator on your smartphone

[berkeman]

A friend showed this to me today, and I downloaded it and am loving it. The HP42 was my favorite calculator, and after my latest one died many years ago, I hadn't been able to find any to buy (at a reasonable price). But now there is a free app that you can download to your phone that brings your trusty HP42 back to life! I'm a happy camper.

Get the app "Free42" from your apps store, or visit the developer's website here: http://thomasokken.com/

 

[ProfuselyQuarky]

That’s cool, @berkeman! I once used a really old one of those that I found in the garage and I was planning to use it for my schoolwork, but the screen was all faded and the calculator leaked ink. So I got a new TI calc to replace it.

I’ll definitely download this, though!

 

[berkeman]

I'm a big fan of RPN, so having my trusty HP42 back is so nice!

 

[dlgoff]

The HP42 was my favorite calculator, and after my latest one died many years ago, I hadn't been able to find any to buy (at a reasonable price).

So I guess I couldn't interest you with this TI?

 

[berkeman]

Not if it has an equal sign = button...

(BTW, that is one WIDE monitor!)

 

[dlgoff]

Not if it has an equal sign = button...

Hard core all the way!

 

[berkeman]

I have to post this funny follow-up for this old thread.

I've been using this HP42 app on my phone at work a lot the last couple of weeks, especially for converting between HEX and Decimal and doing detailed mixed calculations. I was about 3 levels deep in a calculation yesterday, concentrating hard on my calculations, and all of a sudden a text message beeped and the little message icon showed up in the upper corner of my HP42 app.

This confused me pretty badly at first -- I asked myself, "Why is there a text message showing up on my calculator?" It seriously took me about 10 seconds to back out of my intellectual fog and realize that I was holding my phone running a calculator app, instead of holding a calculator. Yoiks!

 

[dlgoff]

@berkeman
Well since you brought up phones. You need to be careful walking around shopping centers, etc. Teenagers walking with phones can and will collide with ya. It's happened to me.

... a text message showing up ...

Evidently I'm going to have to be aware of old engineers too.

 

[Stephenk53]

@berkeman
Well since you brought up phones. You need to be careful walking around shopping centers, etc. Teenagers walking with phones can and will collide with ya. It's happened to me.

Evidently I'm going to have to be aware of old engineers too.

A while ago I almost learned the hard way why it's a terrible idea to text while riding a bike down a hill at full speed, I didn't get hurt but I was lucky I didn't crash

 

[Windadct]

dlgoff - would you be as concerned if you saw someone collided with you while "3 levels deep in a calculation" on a real calculator? Or just think - THERE is a dedicated engineer!

 

[dlgoff]

THERE is a dedicated engineer!

I see your point. Hopefully @berkeman knows me well enough to not ban me.

 

[jedishrfu]

I see your point. Hopefully @berkeman knows me well enough to not ban me.

Don’t worry your TKD Guardian can protect you. If not Berk knows how to repair bans as part of his training.

 

[wle]

I thought one of the attractions of HP calculators was the tactile keys that let you feel that a key press has been properly registered without needing to see it on the display. When I was a kid I had the kid's HP calculator, the (algebraic input) HP 38G. Its operating system was sometimes slow, and I remember I could type in a fairly long sequence of keystrokes -- confident that they'd all been registered accurately -- and then watch as the calculator spent a moment or two to catch up and show the results on the display.

 

[Dr.D]

I'm a big fan of RPN, so having my trusty HP42 back is so nice!

Hear! Hear! I could not agree more! RPN forever! I passed my own enthusiasm for RPN on to my daughter who is also an engineer and she would not dream of using anything else.

 

[CalcNerd]

Well, there is a new upgraded DM 42s available from SwissMicros that you might consider. I bought a DM 41L from them and it has a pretty good keyboard (not quite Hp quality, but feels similar). The DM 42s is everything the Hp 42s should have incorporated. I do plan to acquire but my Hp 42s (with the ridiculous 32 K Ram upgrade) hasn't died so I am not as motivated as others.

 

[berkeman]

DM 42s available from SwissMicros

Interesting! What the heck is that thing? A keyboard and display unit that runs Free 42? I need to know more!

https://www.swissmicros.com/dm42.php

 

[Astronuc]

Close but not quite on topic, is there a reliable HP-41cx app. I still have mine from 1982, and it still works. In fact, I have another that someone was throwing away, but it uses a different batter pack, while mine uses separate N batteries.

I noticed one app with an iOS compatibility issue, which relates to compatibility of apps with new phones. My iPhone is 6 years old, and I'm slowly losing functionality due to incompatibilities.

 

[wle]

So this thread reminded me I meant to see if I could get a hold of one of these at some point.

... and together with a few of its siblings I collected over the years.