[sdiy] Revamped analog shift register works

[David G. Dixon]

> However, there seems to be some issues with the clock circuit, which I
> didn't alter.  For one thing, a sine or triangle doesn't trigger it,
> although it should in principle, since its just a comparator.

Sorry, I'm a bit confused.  There is a differentiator on the input, so an
edge is definitely required.  I was thinking of something else.  However,
all the other stuff I said about the random voltages when clocked with an
LFO is true (and puzzling).