RCA SelectaVision VideoDisc SFT 100 Service Data page 38

CED-1
SAFETY RELATED COPPER PATTERN
Modern circuit design/manufacturing techniques dictate a rather
high component density on the printed circuit board utilized in
this instrument. It naturally follows that the area available for
"printing" copper patterns is also restricted. To maintain high
reliability and safety standards. the printed circuit boards are
manufactured under carefully controlled conditions and to ex-
tremely close tolerances. Some areas of the board are more criti-
са! than others due to spacing. pattern size. voltage/current re-
quirements. etc. RCA has concluded. as a result of extensive
studies that less-than-optimum repair of copper patterns in these
specific areas can degrade the reliability/safety of the instrument.
The critical copper patterns are shown as "dark black" in the il-
lustration (Fig. 5-10). In the event printed circuit damage is evi-
dent in these designated areas (copper pattern broken. lifted.
etc.) special soldering techniques are necessary to maintain
reliability and safety standards. Contact your local RCA Con-
sumer Electronics Distributor Service Manager before attemtping
Copper pattern repair in the designated areas on the board layout.
LET
Fig. 5-10. PW AC IN Circuit Board — Critical Copper
Pattern