The Canon Palmtronic 8M is a handheld calculator introduced around 1976. This model has a brick-shaped plastic case measuring about 77mm x 142mm x 20mm and weighing 118g without batteries. The mottled black plastic case has rounded front edges and metallic gold and black labels. Inside, the main circuit board sits loose on the keyboard assembly.
The 8M uses a 9-digit vacuum fluorescent display (VFD) to show calculations and results. The main display area consists of 8 blue digits, with a 9th digit on the left used for negative numbers, error codes, and memory indicators. Power comes from two AA batteries or an optional AC adapter.
Features of the Canon 8M include the four basic math functions (addition, subtraction, multiplication, division) as well as percentages, square root, and a 4-function memory. The logic allows full 8-digit negative numbers thanks to the dedicated negative sign digit. However, it does not suppress overflow and allows negative square roots. The calculator employs automatic constant on all functions.
The 8M uses a NEC uPD946C microprocessor and other common 1970s-era components like transistors, diodes, capacitors and resistors. Inside, the main circuit board connects to the keyboard with 20 copper wires. The keys have a soft click and good travel. Overall, the Canon Palmtronic 8M provides the expected features for a mid-1970s handheld calculator in an attractive and sturdy case.
There is a different version of the Palmtronic 8 that only has five ridges along the top of the case. Everything else is similar.