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PHILIPS G6 CHASSIS
Two coloured bands, blue and green, move slowly up and
down the screen. They are also present on a monochrome
display. The problem is hum on the signal. First check the
PCF200 colour -difference output/clamp valves for heater –
cathode leakage – preferably by substitution. If the trouble
persists, the most likely cause is hum on the 1.t. lines,
probably due to C1019/20/21. Make sure they are properly
earthed before replacing them.