Panasonic GP6DU - TH-42 PD25 U SC and SS SOS Detect

TH-42PD25U 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 30 - SC board SOS Detect
52