4 Oct
1999
4 Oct
'99
9:19 a.m.
Tim Shoppa wrote:
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.
This was known by the trademark "Multiwire", and was often used for
quick-turn production. DEC used it on a few boards in the KL10-PV
processor; later revisions of the same boards were conventional PCBs.