Model: HP-19C
Battery:
Adapter:
Year: 1977-1979
Chip:Info: The HP-19C and HP-29C were scientific/engineering pocket calculators made by Hewlett-Packard between 1977 and 1979. They were the most advanced and last models of the "20" family (compare HP-25) and included Continuous Memory (battery-backed CMOS memory) as a standard feature.
The HP-19C included a small thermal printer, one of the very few hand-held scientific calculators to offer such a feature (HP-91, HP-92 and HP-97 were desktop units and later models like the HP-41C only supported external printers). Due to the printer's power requirements, the 19C used a battery pack of four AA-sized NiCd cells, adding to the weight of the calculator and printer mechanism.
The coolest thing we have with the HP-19C is having the HP logo at the point used as a comma by the calculator. A special thanks goes to Alessandro (alexanderpentagon) who helps me with the HP.