Mitsubishi Electric WS-48513 Troubleshooting Manual page 46

SHORT Detect
The short Detect circuitry is shown in Figure 4-6 and is
the same as in the V19 and V21 chassis. If a short
occurs in the + or – 24V supplies, pin 46 on IC7A00
goes Low indicating a short and the TV shuts Off. With
-24V shorted, the 12VS supply turns Q9A53 On, pull-
ing the SHORT line Low. If +24V is shorted D9A54 is
forward biased and the short line goes Low.
X-RAY Protect
Refer to Figure 4-7, the X-Ray input is at pin 47 of
IC7A00, and is normally High. The X-Ray Protect
circuit monitors:
• Excessive HV
• Excess CRT Beam Current
• Excess HV circuit Current
If any of the preceeding occurs, the X-Ray line goes
Low, and the TV shuts Off.
IC7A00 Additional Inputs
Pin # Name
6 SD-SUB
7 SD-MAIN
62 H-SYNC-IN
64 V-SYNC-IN
92 AFT1
93 AFT2
94 VBLK
97 CV-IN-SUB
100 CV-IN-MAIN
Table 4-1: µPC Inputs
The monitoring circuits for X-ray Protect are described
in the detail in the Deflection and HV Section. Other
parallel inputs to the µPC, are listed in Table 4-1.
Source
Sub Tuner Sync Detector
Main Tuner Sync Detector
ASIC Horizontal Sync
ASIC Vertical Sync
Main Tuner AFT voltage.
Sub Tuner AFT voltage
Deflection Loss Detect circuit
Sub Video (CCD, V-chip,etc)
Main Video (CCD, V-chip,etc)
4-6