The service manuel is very helpful, we where able to restore the device to its working operation again.
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IC DESCRIPTION-6/6 (NJW1300A)-2/4
Pin No. 20 Pin Name BYIN I/O I Description Input terminal to the color difference demodulation circuit when the PAL system is selected. This terminal is open when NTSC system is selected. 21 PICTURE I The Y signal frequency response characteristics are changed for image enhancement. The Y signal image is enhanced by increasing the voltage of this terminal. 22 23 24 25 EXTINB1 VCC1 YINH EXTINB2 I I I I The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. Connect this terminal to 5 V power supply. Y signal high frequency component input terminal. The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. 26 YIN I Y signal input terminal. Input the Y signal that has the standard input level of 350m Vp-p. 27 28 29 30 31 EXTING1 SW1 EXTING2 SW2 EXTINR1 I I I I I The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. Selector control signal terminal that selects either INT signal or EXT signal. The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. Selector control signal terminal that selects either INT signal or EXT2 signal. The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. 32 GAINR I R signal gain fine-adjustment terminal. This terminal is open usually. 33 EXTINR2 I The terminal to which external analog RGB input signal is connected. Input the primary color signal that has the standard input level of 700m Vp-p. RGB signal gain variable control terminal. 34 CONTRAST I Amplitude of the RGB signals are interlocked and adjusted by the voltage applied to this terminal. 35 GA CLAMPR 36 GAINB GA CLAMPG I � An external clamp capacitor is connected to this terminal to clamp the R signal pedestal. Use a capacitor with small leakage. B signal gain fine-adjustment terminal. This terminal is open usually. 37 � An external clamp capacitor is connected to this terminal to clamp the G signal pedestal. Use a capacitor with small leakage. The variable control terminal that determines the first gamma deflection point at the low 38 VG1 I brightness in the gamma correction characteristics of the RGB signal. This voltage is internally preset and RGB signals are interlocked. The variable control terminal that determines the second gamma deflection point at the low 39 VG2 I brightness in the gamma correction characteristics of the RGB signal. This voltage is internally preset and RGB signals are interlocked. 40 GA CLAMPB � An external clamp capacitor is connected to this terminal to clamp the B signal pedestal. Use a capacitor with small leakage.
