4 Oct
1999
4 Oct
'99
12:01 p.m.
Dave McGuire wrote:
PhotoCircuits on Long Island was IIRC involved with it at one time. I don't
recall if they were a part of Kollmorgen (sp???) at the time or not, but I
saw the Multiwire machines working, and they were rather interesting to
watch!
The PC boards
that make up the backprojector make use of a unique
technology: the PC boards themselves are just plain old two-layer boards,
with the actual PC traces carrying only power and ground. All the actual
wiring is done by fine machine-laid wiring between pads, with all
the wire layers "potted" in a plastic compound. Obviously, reworking
such a PC board is extremely difficult, but it gives impressive component
densities for the time. The modern equivalent of this is multi-layer
PC boards, naturally.
I've seen a lot of those boards. They weren't a predecessor of multi-layer
PCBs per se. Some company (I've long since forgotten their name) sold the
system that created those boards...it was an in-house system so that you could