[sdiy] Random Voltage Generation

[Grant Richter]

Interestingly, the primary financial incentive for development of analogue
computers dates back to the 1500's. As far as I can tell, rapid solution to
the multivariable equation of cannon shell trajectory provided the initial
funding. (shell weight, powder charge, barrel angle and wind effects into
distance)

Aiming guns then provided most of the funding for research for the next 400
years. Initial analogue computers were mechanical, but electrical designs
were used as quickly as possible. WWII battleships had analog gun control
computers.

The transition from military to industrial use probably occurred when
military designers went back to peacetime work.

In this case, it is not swords into ploughshares, but gun controls into
musical instruments. Any reasonable sized modular could still be used to
solve cannon trajectories (in a pinch ;^)

> 
> It seems like most of the technology for electronic synthesizers was taken
> from other sources, which is consistent with musical instruments making use
> of their age's technology.  A friend in the area used to work at an analog
> computer manufacturer in Eatontown, NJ which is now defunct.  They had a
> module there called an "arbitrary function generator", which sounds just
> like an analog sequencer.  It had enough stages they were able to take two
> of its outputs, attach them to the X and Y input of an oscilloscope, and
> make detailed pictures on the phosphor.
>