The HP-46 internal view

This HP-46 desktop calculator needed a thorough cleaning. I decided to open the calculator and also clean its interior.
The opened calculator gave me a chance to make some photo's of its interior.

The photo above shows the HP-46 with the top housing removed. The large printer module is clearly visible.

 

This photo shows a close-up of the printer module. This printer module is the Model 102 from Shinshu Seiki.
The ink ribbon has been removed. On the right side of the printer the power supply is located.

 

The photo above shows a close-up of the Option 001 Display print. This print fits in an
edge connector on the PCB. The printer module has been removed.

 

For this photo the keyboard, display print and printer are removed. The large PCB covers the complete
bottom of the calculator. The driver IC's for the printer are located under the printer. See the 'top' part of the middle section.
The CPU and memory chips are located in the 'left' section.

 

The keyboard module. A solid keyboard build on a metal frame.

 

The main PCB which contains all the electronics. A standard two layer design with a lot of space for the components.

 

HP-46 inside related links:

• Schematics drawn by Tony Duell can be found here.
• Shinshu Seiki (later Seiko) Model 102 printer module