Secret Diagram

Used ICs: TDA9352PS/N21/3-OTP, 24C04, LA6510, 346VF2(Infrared sensor), KA5Q0765R | KA5Q0740RT(120v) | KA5Q0765RT (220V), KA7632, FCA173B(FBT), NJM2235D, AN7522N, MSP3425G-B7 and TDA6107Q [NTSC system – North America, South Central America and Mexico]
FOCUS Adjustment
1. Input a black and white signal.
2. Adjust the tuning control for the clearest picture.
3. Adjust the FOCUS control for well defined scanning lines in the center area of the screen.
Factory Adjustment
To enter the “Service Mode”, Press the remote-control keys in this sequence :
- If you do not have Factory remote-control
Picture OFF > Mute > 1 > 8 > 2 > Picture ON
- If you have Factory remote-control
Picture ON > Display > Factory

Following is the protect circuit Samsung TV which use IC LA76931 as basic working the protect circuit. This Protect Circuit LA76891 located at pin-30 whichconnected to the collector of transistor Q902.In normal conditions the voltage at the base of Q902 is "low" and the voltage at pin-30 is "high". For the temporary crippling protect, it can be removed Q902 (or to the emitter-base short).

Vertical Protect. Pulses of the vertical-out rectified by diode D355, so that the base voltage is approximately 0.6V Q904 ,and collector voltage is 0v.

X-ray Protect (option). Sampled using a heater voltage of the circuit as shown below. Normal vltage in x-ray path to the base of Q902 is zero.