C47/R47 Calculators

21 pointshelterskelter3 days ago9 commentsView on HN

From 2025 and order process is defunct.

here you go: https://www.swissmicros.com/en/products/r47

It was restocked the other day, SwissMicros had an issue with the button domes and had to wait for replacements to come in from China which took awhile because of Trump/Iran.

helterskelter2 hours ago

I forgot to add that development is active:

https://gitlab.com/rpncalculators/c43

zokier3 hours ago

There is also another major DM42 firmware project: DB48x https://48calc.org/

loloquwowndueo3 hours ago

Still looking for the perfect replacement for my HP48GX which died a mysterious death. Actual 48GX are hideously expensive and I’d be concerned they could also just mysteriously kick the bucket.

whartung2 hours ago

Today, the thing that makes the HP48 series much less useful is simply that they lack a backlight.

I find them simply difficult to read and use today because of that.

So, I just use a HP48 app on my phone. It's not as good, lacking the tactile response of the keyboard. But it's close.

I used to program the 48's. You think laptops are convenient, wait until you try coding in bed on a 48. Very comfortable, if you can stay awake :).

loloquwowndueo2 hours ago

Dunno man, I did just fine with my 48 and I do just fine with the crappy lcd scientific calculator I have now, but it’s basic and doesn’t hold a candle to the 48.

Did do a fair bit of programming in the 48 too :) fun shit.

sunpazed1 hour ago

I’m a vintage calculator tragic! I love what the C43/47 communities are doing in reviving RPL and RPN for a modern audience. What’s even more amazing, is that the DB48x calculator is a singular dev effort by the talented Christophe de Dinechin (I’ve contributed briefly to his code).

If you’re curious to try out RPN/RPL without buying hardware, then both the R47 and DB48x calculators are available as apps on the iOS App Store.

Those of you who want to go deeper down the rabbit hole, I strongly recommend you check out Calculator Culture — he reviews both modern and vintage devices; https://www.youtube.com/@CalculatorCulture