Alex Garza Brings Back Not One, But Two Iconic HP Calculators with the AVR128DA-Powered PX-VOY

Maker and vintage calculator enthusiast Alex Garza has released a kit to build an emulator of Hewlett-Packard's classic HP-15C and HP-16C calculators — software-selectable, and both running atop a Microchip AVR128DA microcontroller: the PX-VOY.

"The PX-VOY is a DIY calculator kit that faithfully emulates the iconic HP-15C and HP-16C," Garza explains. "Both top and bottom panels are reversible: one side labeled for the 15C, the other for the 16C. Embark on a fun and educational experience by building your own calculator. Ideal for electronics enthusiasts and fans of classic HP calculators, the PX-VOY offers both a rewarding project and a powerful tool."

Garza first demonstrated the kit earlier this year on the Museum of HP Calculators forum, where fans of the HP-15C and HP-16C — the former HP's first to add support for complex numbers and matrix calculations, the latter aimed at programmers with support for hexadecimal, decimal, octal, and binary representations with a word size configurable from one to 64 bits — expressed their admiration for the design. Like Garza's earlier kits, the front panel is a PCB that uses copper and silkscreen layers for labeling soft-touch keys which poke through cutouts — with a larger cutout for the display, a low-power monochrome LCD with a 250×122 resolution.

The new design upgrades on its predecessors, though, with a shift to the more powerful Microchip AVR128DA microcontroller — "faster," Garza explains, "more storage, and still eight-bit" — and includes a serial port for communication with a desktop machine. "The [serial] format is compatible with the SwissMicros web decoder/encoder," the maker notes, "and should also work with Pierre's Excel decoder/encoder."

The PX-VOY is available to order on Garza's Tindie store, priced at $99.99 as a kit of parts or $124.99 fully assembled. More information is available in the project's thread on the Museum of HP Calculators forum.