Mitsubishi Electric WS-48513 Troubleshooting Manual page 64

Q5A20 and its associated circuitry comprise an Arc
Protect circuit. If a CRT Arcs this circuitry immedi-
ately removes HV Drive.
If X-Ray Protect shuts the TV Off, pressing the Power
button will turn the TV back On (it may shut Off
again if the problem still exists). If Arc Protect is
activated, the TV must be switched Off before it can
be switched back On.
6-10