Saturday, September 28, 2019

HHC 2019: The Videos (Eric Rechlin) and Commentary

HHC 2019:  The Videos (Eric Rechlin) and Commentary

My favorite time of the year:  HHC (HP Handheld Conference) 2019, which took place in Reno, Nevada on September 21 and 22, 2019. 

I was blessed to be able to go this year, it's always good to meet with close friends again. 

The conference was all about classic RPN calculators, primarily the HP 41C, Swiss Micros DM41, HP 42S, and Swiss Micros DM42.    The DM42 is becoming my preferred calculator. 

Thanks to both Eric Rechlin and Jake Schwartz for the videos and editing.

Cubic Chess - Jeremy Smith

Want to have a chess board everywhere you are but you are not a fan of how much space the board takes?   Cubic chess solves this problems by putting all the chess pieces, from rook to queen to king, in a form of a cube.  Cubic chess was first created by Graham Lanier in 1966.

Shop Projects Update - Jim Donnelly

Cubic Chess set - Jim Donnelly

Jim Donnelly updates us on his latest projects:  a cubic chess set, harmonic transformer, a beautiful cometarium, Genaille-Lucas Rulers, and Napier's bones. 

Cometarium - Jim Donnelly (also in the pic:  HP 12C (cut-off), HP 32S, HP Prime G2, DM42)

A cometarium is a classic mechanical device that calculates the position of celestial objects, such as Halley's Comet and the Moon, depending on the time of year.   Genaille-Lucas Rulers are a set of rules, created in the turn of the 20th century, as a device to aid in multiplication and division.  Those rules confused me. 

SwissMicros DM41X Announcment - Bob Propseri

The next product to come from Swiss Micros is the DM41X, a four line calculator that runs HP 41C hardware.  Features include USB storage and saving calculator states.  All 41C software and mods will run on the DM41X.  The calculator is set to be released in early 2020.

Newton Method Interpolations - Namir Shammas

Shammas introduces a Newton's Method that uses a modified central difference method to calculate the derivative. 

Overview of the WP 34C - Günter Schink

Adopting a Swiss Micros DM42 machine to run WP 34C software.

My Role as an Archivist; or, What's on the HHC USB Drives

One benefit of attending of an HHC conference is that you get a USB drive that is full of documents, manuals, and articles involving calculators, primarily Hewlett Packard, but other brands get some coverage. 

You can order a HHC 2019 USB drive from here - cost is $40 US dollars:

What's New in the PPC Archive DVD - Jake Schwartz

New additions to the PPC DVD, which are included in the 2019 USB drive mentioned above.

Percent Change, Logarithms, and their Interpolation - Richard Schwatz

Schwartz introduces a new approach to calculating percent change.

Impromptu Report from Across the Pond - Bruce Horrocks

Multi Variable Solver - Namir Shammas

Shammas presents how you use vectors or arrays to aid in solving equations where you can solve for any variable.

The Nature of Time - David Ramsey

Bulova Accutron watch (1960) - David Rasmey

Ramsey has a beautiful presentation of the history of time making devices, including sundials, Egyptian water clocks, fusee, and super expensive and exquisite chronometers.

Graphics on the DM42 - Jim Johnson

Johnson presents how to generate graphics on the Swiss Micros DM42 (and by extension, HP 42S).  The DM42 has three sizes for graphics output.

Percentages on the 48 - Richard Nelson

A technique on how to work with percentages on the HP 48S/48G family.  This is one of the few talks the focus is on other calculators. 

RIP HP Calcs - Richard Nelson

USB Power - Richard Nelson

How to measure current and voltage with a USB powered device.

Woodstock Low Power and ConnKit - Bob Prosperi

The kit that will update the classic HP Woodstock series from the 1970s (HP-21, HP-22, HP-25, HP-27, HP-29). 

The Financial Calculators (via Skype) - Gene Wright

Think that all the financial calculators came from Hewlett Packard and Texas Instruments?  Nope!  Wright presents the history of the financial calculators during the 1970s.  There is one particular model that gets repeated cloned by many companies, see if you can spot it.

Scout Evolutionary Optimization Method - Namir Shammas

The Scout Evolutionary Optimization method aims to find global optimum (extrema, minimums and maximums) of a function. 

DIY Calculators - Joey Shepard

Shepard, while saving up to purchase an HP 48, turned his Casio Algebra FX 2.0+ into an RPN programmable calculator.  Shepard also presents two small RPN calculators he created.  He is the HHC 2019 Best Speaker.

Aural Clocks and Big Ben on the 48 - Tom Chrapkiewicz

Chrapkiewicz continues his HHC 2018 talk, this year he shows how to use the HP 48G as a clock which beeps every five minutes.

The HP 39G/49G Overhead Projector - Bruce Horrocks

Horrocks chronicles on his journey of fixing the projector for the HP 48SX and HP 39g/49g.

On a side note:  I saw projector for the TI-82 and TI-83 Plus at a local Christian thrift store, but I didn't buy one.

HHC 2019: Programming Contest Winners

The contest:  find all four 3-digit numbers where the cube of its digits are equal to the number itself.  Example:  153 is one of the four because:

1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153

Check out some of the community's solutions here (starts on page 2 of the thread):

Door Prizes

The big door prize was an HP-75C.  The HP 75C was a large BASIC computer that was sold in the mid 1980s.  The intial memory was 16,000 bytes which could be extended, with a ROM card, to 48,000 bytes.  More information can be found here:

As for me, I won some much needed calculator cases.  There were a lot of books, of various subjects, and a few calculators that were up for grabs.

That weekend went by so darn fast! 

By the way, I recommend the Redwood Rotisserie + Grill in Reno.  The food is so good!

My Quick thoughts on the future of Hewlett Packard Calculators

There was no talk about the HP Prime this year.  Hewlett Packard is slowing down when it comes to calculator production.  Sad to say that there is almost no new development for the HP Prime, nor any development for future scientific calculators. 

I don't think HP is going away completely, but as far as calculators, the focus will be on its finance models (primarily the 12C, 10BII+, and 17BII+). 

The future on these conference is going to depend on independent developers such as Joey Shepard, Swiss Micros, and everyone who develops emulators, Olivier De Smet comes to mind, for smartphones and tablets.  I am encouraged that there is an enthusiasm for mathematics, calculators, and other calculating devices. 

The HHC 2019 conference web site is here:  Keep an eye out for the HHC 2020 conference, probably around late winter of next year. 

Happy Calculating,


All original content copyright, © 2011-2019.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.


  1. Typo in topic: Overview of the WP 43C - Günter Schink

  2. Great overview! Regarding your closing comments; I think HP focuses on financial calculators indeed (if calcs are on the management radar at all!). My fear is that ultimately they won't offer any RPN programmable calculators at all anymore ... I could live with the HP 17Bii+ but not with no RPN option at all (of course, technically the HP 17Bii+ is not programmable, but the equation solver is very rich).
    What I really hope is that they come with a successor for the HP 35S, with better battery life, and (most importantly) I/O capabilities. But I fear that will remain a dream.


Numworks Update 17.2 - Highlights

 Numworks Update 17.2 - Highlights Update is available at: The Numworks website will detect your calculator and wi...