SwissMicros DM15L RPN Scientific Calculator – HP-15C Inspired Upgrade Programmable Functions, Algebra, Calculus, Physics, Engineering, Graph, Matrix, Solar Power for College, High School, Students

Excellent re-make of the HP workhorse!I have been searching for years for an HP-15c calculator. All I could ever find for decent prices were used HP-11s units, which, while nice, are financial in nature and not really useful for my own engineering work. I love the landscape layout and RPN entry system. Once you learn and become used to this layout and entry method, "regular" calculators seem painfully clunky.SwissMicros makes these "clones", using the original HP microcode. This means they give the same results, and have generally the same 'quirks' that the original HP models exhibited. But with larger memory storage, 4x the speed, sturdy metal cases and wonderful clicky keys.They're firmware upgradable, include a real-time clock, user selectable operating speed (12Mhz or 48Mhz), three display fonts for your viewing pleasure and long battery life off a single CR2032 coin cell. Perhaps not the decades we got from the LR44/357's in the original HP models, but certainly many months or years depending on your usage patterns. Easy to replace when needed with four screws.Nice heft to the unit, feels very nice in your hands. The keys are clicky, giving very good tactile feedback on button presses, with a solid feel to the whole thing overall.Am I pleased with my purchase? YES, very pleased.Would I purchase again? OH YES! I actually have this unit on my desk, and a smaller version (the DM-15 credit-card sized) in my purse. Don't leave home without one!

I like the DM15L as much as my HP11C. Faster and 40 years newer.Swiss Micros is about the only game in town for new RPN calculators. I collect them, I use them. I use the DM15L in my living room with the big TV while surfing the web. Handy for those quick calculations that don't require any programming. I always liked the Voyager (Landscape design). Screen is very readable. Buttons are fine. I also bought the DM15 credit card sized version which is a great novelty, but the buttons are too stiff to use as a daily driver.Cheerleading for Swiss Micros below:My HP41CV has broken posts, bad z-strips, and battery terminals. With manipulation, I can sometimes even get it to power on. My HP41CX is still in great condition except for the battery terminals. It faithfully powers on, but I know it will probably quit before I do. I got the DM41X masterpiece to replace those two. The DM41X improves on the HP41CX with many conveniences like the custom menu and USB interface that simply make the DM41X my daily driver on my desk. The custom menu supplants the plastic overlays from the 41's that let us repurpose seldom-used keys.The DM41X claims to support overlays, but didn't come with any, and my attempts to use a Cricut to create overlays for the DM41X have been promising, but ultimately disappointing largely due to the thin, flimsy overlay requirements. The old 41 overlays were at least three times thicker than what can be used on the DM41X/DM42.I have the HP 49 and the HP Prime (which will likely be my last HP), but my glory days were with the 11 and the 41 series. Swiss Micros understands that bond and has excelled in feeding my passion for these classic calculators.

It replaced my old HP 15C calculator and it is a very capable scientific calculator as the original HP 15C is.However, perhaps I have received a used product, since the coloring of the key function letters are faint and hard to see in the low light. The old HP 15C had better colour contrast for the key function letters. Otherwise, if you are looking for a portable and useful scientific calculator with a long battery life, you may not find any better calculator (I wish the original HP 15C was continued to be produced, I really missed it).

Ok so some of you probably know a weirdo like me who collects calculators. I know I'm not normal, I long y calculators. I don't even really use them for work but I never got over how useful they were.Anyway growing up I used my Dad's HP 11C which my brother ultimately lost. So about a decade ago I went and bought my own used HP 15 C and one for Dad as it was superior to the 11C. I loved it. But the calculator was showing it's age.I used my Dad's 11 C in calculus in highschool and ultimately upgraded to a Ti 89, and an HP 48 G series.One thing I loved about the HPs was RPN. Anyway I deployed to Iraq and while overseas I missed the opportunity to buy the HP 15 C limited edition. These days you can buy them but because of how few are out there you need to purchase a second hand item at prices upward of $1000.When I discovered the Swiss Micro DM 15L I couldn't pass it up. It arrived in a timely manner, especially considering it shipped from Europe. But more importantly this machine rocks.I don't have a 15C limited to test it against, but it certainly is faster than my older model. This calculator uses the exact same voyager layout as the 15C, the feet are sturdier, has a USB port, uses RPN, and is without a doubt my new favorite calculator.If you know someone who collects calculators this is definitely one to give them. I absolutely love everything about it. The keys, the machine work that went into the casing. This calculator is great.

I got this as an upgrade for my old HP-11C and I am very impressed with the quality you get for the price. The keys have a very positive feel and the display can be adjusted for contrast. You can even change the font. It functions blazing fast and reproduces all the functions of the original HP-15C.When it arrived, the display had some pixels that wouldn't turn off, but I followed a simple procedure that Michael from Swiss Micros emailed me and now it's fine.For quality and customer service I give it 5 stars.