I wonder what he means by 'cardboard' circuit
boards though
I think it was a dig at Sylvania's (indeed the industry-wide) standard PCB technology
of the time.
Today we are very used to etched PC boards with a fiberglass epoxy substrate and copper
traces that were etched.
But the original consumer-type PCB technology was more often formica or phenolic-type
circuit boards with traces that were stamped from sheet foil and then glued to the
phenolic. (There was also a mil-spec type of PCB that was a ceramic base with silvered
traces essentially painted on - you see stuff like this in Tek scopes of the 50's and
60's.)
Not surprising to see Sylvania mentioned in the same breath because of course Sylvania
used the phenolic PCB technology across many of their consumer TV's and radios.
The cheap 50's and 60's phenolic PC boards are indeed like plasticized
chipboard/cardboard. I'm 99% sure that phenolic is still being widely used in consumer
electronics (although it is a higher grade than that from Sylvania's 60 PCB's and
you might not know it's really plasticized chipboard until you break it.).
DEC modules from the 60's were most often a high grade (for the time) phenolic PCB.
Glass Epoxy really took off in the 70's. I'm thinking the Foxboro 1 pictures are
from the early 70's and represent a later implementation of the Sylvania architecture.
Fingers on phenolic PCB's are far less durable than fingers on glass epoxy PCB's.
I never used a Fox 1, my earliest exposure was the Fox 2/30.
Tim.