There's a very good star-chart program that's been around for many years, called Astrolog [0].
Although it's obviously intended for astrologers, you don't have to believe in astrology to find it useful. Maybe you just want to know whether that bright light near the moon is Venus or Jupiter, or when is the next time Mars will be easily visible.
I was always a bit puzzled by the ubiquity of astrology and other superstition in old scifi (PKD, Heinlein to name a few), but I guess if even Reagan used things like this that explains where the trope came from.
Very curious find! I wonder what sort of calculations it's doing. Anything that would be useful to an astronomer? Or just weird bunko? Are the calculations deterministic?
There's a great book called Practical Astronomy with your Calculator; I wonder what the astrological analog would be.
Nice to know the (ex-) leader of the most powerful military machine and protagonist in the cold war used this to make 'better' decisions.
> This is the same Digicomp which made two mechanical "computer" models, or toys
I doubt it is the same company. Those toys were made by E.S.R., Inc., whereas the DR70 is by Digicomp Research Corporation, which apparently still exists. A cursory search didn't reveal any connection between the companies.
I wonder which key switches it uses.
There are also circuit diagrams for 'e-meters' ... presumably targeted at a similar crowd.
http://www.cs.cmu.edu/~dst/E-Meter/