chake propper filament voltage and final anode and focus voltage ,make g2(screen )voltages apx 280v in a standerd digital meter.then chake ik voltage at pin 18 of 8844 it shouldbe more then 4.7v if not chake for proper rgb drive from 8844 it may faulty if not u have to measour all the components at crt ckt and replace all 9 tr at crt pcb.note that some time eprom coruption couse this fault too.