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Frank's electron Tube Data sheets Friden 1112  

This is what's left of my Friden 1112. I took it apart a very long time ago to use the case for a micro processor system. I should not have done that;-)
For half the boards I drew the schematics. Maybe someday I will finish it...
For some more info about this machine, see: The Old Calculator Museum or Calcuseum
main frame circuit
board 1 circuit
board 2 circuit
board 3 circuit
board 4 same as 3
board 5 circuit
board 6 circuit
board 7 circuit
board 8 circuit
board 9 tbd
board 10 tbd
board 11 tbd
board 12 tbd
board 13 tbd
board 14 tbd
board 15 tbd