Early Electronic Calculator Canon Canola 120 Calculator

Manufacturer:  Canon Model:  Canola 120 Year:  1967 Form:  Desktop Functions:  Basic four, accumulator Number of Digits:  12 Display Type:  IDL Logic Technology:  DIS Memory Technology:  DIS-FF Diodes:  Lots and lots Transistors:  489 (not including power supply)

Information for this unit was provided by Shigeru Masuda of Japan. Much as Jean Campioni with his Canon 130S, Masuda was able to use the Canon 161 schematic to assist in servicing the 120, and then sent along the information presented here.

The Canola 120 is a variation on the Canon 130, the 120 having 12 digits instead of 13. There are some minor alterations in the keyboard layout as well.

Interior view.	Backplane with new edge connectors. The boards were originally soldered to the backplane, as in the Canon 130. For servicing, Masuda disconnected the boards and installed edge connectors so the boards would be removable.	Closer view of the new edge connector installation.
In addition to the backplane connections, the display connections had to be dealt with. These header socket/plug pairs were installed on the boards and spliced onto the wires from the display.	One of the fault points Masuda found in servicing the unit: a cracked solder connection on a feed-thru stub connecting traces on the two sides of board 8. This is a very common type of failure on machines of this era, although in this machine board 8 is the only double-sided board.	Component-side view of board 8 with overlay of the traces from the solder side. While using the Canon 161 schematic for insight into the 120 circuitry, Masuda produced these images for each board to assist in tracing.
Board extenders constructed for servicing.