Th-42Xvs30 Sc And Ss Sos Detect - Panasonic GP6DU Technical Manual

TH-42XVS30 SC and SS SOS Detect

The Scan and Sustain voltages on the SC and SS boards are monitored in a
similar manner. The +15V Line on the SS board is fed to a voltage divider and
the result is compared to a reference voltage. The reference voltage is provided
by a zener diode. If the output of the comparator goes high, a transistor turns on,
effectively grounding the SOS line. The SC board uses a similar circuit.
Additionally the SS and SC boards contain LED indicators to alert the technician
when a problem exists. The LED should be lit during normal operation, a dark
LED indicates that a problem exists on that board.
Figure 41 - SS SOS Detect Circuit (TH-42XVS30)
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