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I have an old HP 15C RPN scientific calculator. - I know where the buttons are without looking. - It has functions my Android calculator does not have (direc

I have an old HP 15C RPN scientific calculator. - I know where the buttons are without looking. - It has functions my Android calculator does not have (directly or that I know of). - It has a strange satisfying tactile feedback. - It never interrupts me. Ever. - It never distracts me. Ever. I reach for it frequently.

silvestrov 8mo ago
I've never owner any other piece of technology with buttons this good. It is really a lost art.
rented_mule 8mo ago
I can't think of another electronic device that has survived and remained useful for half the 43 years my 15C has - through two years of high school, a math degree, and an entire software engineering career. When I calculate something any other way, it involves thinking about what my thumbs automatically do on my 15C and translating that. When I'm away from it, there's a wonderful emulation of the 15C (and 16C) at https://jrpn.jovial.com https://jrpn.jovial.com. The numeric algorithms behave identically as far as I can tell, and it even includes the back panel (3-dot menu near the logo, then "Help"). The visuals make me feel right at home. If only they could reproduce the tactile experience.
commakozzi 8mo ago
IMHO the HP 15C RPN is the best calculator ever made. I still have the original with the slip case and manual. However, more often these days i just use my phone's calculator without RPN (i don't need to do a lot of complicated math for mechanical engineering -- we use tables for most stuff). I reached a point/decision several years ago to protect my HP 15C for posterity.
kqr 8mo ago
I smilarly use the HP 12c. There is nothing more convenient for solving simple compound interest/discounting problems.
pseudohadamard 8mo ago
I have some generic Sharp calculator with an apparently-immortal battery and a nice multiline display. It has all sorts of fancy functions that I never use. Apart from that, everything the OP said.
zippyman55 8mo ago
I still have mine too! My non-techncial wife learned to use it, and I smile everytime she used RPN.

silvestrov 8mo ago

I've never owner any other piece of technology with buttons this good. It is really a lost art.

rented_mule 8mo ago

I can't think of another electronic device that has survived and remained useful for half the 43 years my 15C has - through two years of high school, a math degree, and an entire software engineering career. When I calculate something any other way, it involves thinking about what my thumbs automatically do on my 15C and translating that. When I'm away from it, there's a wonderful emulation of the 15C (and 16C) at https://jrpn.jovial.com https://jrpn.jovial.com. The numeric algorithms behave identically as far as I can tell, and it even includes the back panel (3-dot menu near the logo, then "Help"). The visuals make me feel right at home. If only they could reproduce the tactile experience.

commakozzi 8mo ago

IMHO the HP 15C RPN is the best calculator ever made. I still have the original with the slip case and manual. However, more often these days i just use my phone's calculator without RPN (i don't need to do a lot of complicated math for mechanical engineering -- we use tables for most stuff). I reached a point/decision several years ago to protect my HP 15C for posterity.

kqr 8mo ago

I smilarly use the HP 12c. There is nothing more convenient for solving simple compound interest/discounting problems.

pseudohadamard 8mo ago

I have some generic Sharp calculator with an apparently-immortal battery and a nice multiline display. It has all sorts of fancy functions that I never use. Apart from that, everything the OP said.

zippyman55 8mo ago

I still have mine too! My non-techncial wife learned to use it, and I smile everytime she used RPN.