13 Nov
1998
13 Nov
'98
5:29 a.m.
Several times in the past I've seen home-brewed and perhaps
CPU-driven signs that consist of a single vertical line of
perhaps a dozen or two LEDs.
The "sign" doesn't appear to be anything but a line of glowing LEDs.
Only when you view it at a glance, as your vision moves quickly
from side-to-side, do you see that it is rapidly
flickering the
vertical scanlines of a simple dot-matrix image: maybe the digits
of the time, perhaps a smiley face, or some other simple image.
Anyone here know the name of this sort of device, so I can web-search
for others who've made one? It wouldn't be hard to craft. To be
obliquely on-topic, I've thought about making a simple circuit that
would be driven by the parallel port of an old PC.
- John