It wasn’t the exact calculator that I was looking for, but the purchase was well worth the price paid for it. The model 425 from Litton Monroe is a 12 digit Panaplex display with memory calculator.

Barbouri's Electronics Projects
Restoring vintage electronics along with designing and building new circuits. One eye looking into the past, the other looking into the future.
It wasn’t the exact calculator that I was looking for, but the purchase was well worth the price paid for it. The model 425 from Litton Monroe is a 12 digit Panaplex display with memory calculator.
I decided to see what I could do about the temporary modification to the Burroughs C 3207 multiply key indicator, before it became a permanent modification.
Another nice calculator find for the collection is my CS-2115. It is a 12 digit calculator with a vacuum fluorescent display, memory, and several extra functions.
Well I just finished working on the APF Mark 1 calculator so I wasn’t looking for another calculator project right away, but I stumbled upon this Burroughs C 3207 calculator with several issues for a price that was too good to pass up. And it’s a vintage 14 digit Nixie tube calculator Built in late 1969.