Additional Pictures 


The backside of the SR-40 Prototype with the Serial Number 0000030. 

The printed circuit board (PCB) of the SR-40 is similar to the later SR-16 II. 
Please notice the different arrangement of the battery contacts, 
the TMS1111 single-chip calculator circuit and the small coil
of the power supply. 

Close-up view of the TMS1111 single-chip calculator circuit. 

horizontal rule

If you have additions to the above article please email:

Joerg Woerner, March 13, 2013. No reprints without written permission.