ETD's

[Newton Hunt]

The big leap came when Al Sanderson SAT (800-FAST-440), using an 8 bit
microprocessor, converted an incoming analog signal to digital and,
using a large crystal, compared the phase of the two and displayed the
difference using the rotating LEDs.  They don't actually rotate, just
some stay on longer than the others and give the illusion of
rotating.  The internal signal is derived mathematically, from an
internally calculated scale from input measurements or from a
memorized scale.

More than you ever wanted to know, right?

I can sell you an SAT.

	Newton