From the phenomenon analysis, suspected fault in the high frequency head or intermediate frequency processing circuit. Try from the intermediate frequency circuit input into the signal, fault remains the same. Indicates that fault is not in high frequency. Then check into the integrated block IC1F (LA7522) voltage is normal. From IC1F22 feet (video signal output) injection signal, the fault is still, apparently, the fault is not in intermediate frequency circuit. Again from the AV socket into video signal, the result picture is normal. On this basis, to show that the fault into video signal output to the video switch between. Check is putting video output capacitance C822 (47 (including F / 16 v) almost completely without charge and discharge phenomenon. Change after the commissioning, troubleshooting.YpQservice manual download site