1994 samsung CH-CKA50ZH model: CT--5315XVC screen blinking

[a obsessed guy]

my tv flashes/blinks after 5 seconds i turn on. i've noticed that if i lower the brightness setting in this tv, to almost dark, it wont flash/blink, but if it's bright, it'll flash/blink? any help? is it 'cause of the magnet wire around the tube that's out of the properly place? if so how do i fix it? is there something wrong on the circuit i need to resolder? if so, where exactly? schemtic if possible? i know how to repair circuits with solder stuff, i've done many time on computer circuits and console circuits, so im sure a tv circuit's similar.
pardon my english.
thanks in advance.

p.s.
this occured three times before, after i shook my tv, blew dusts off my tv circuit, etc, no resoldering, it stopped flashing/blinking, ran fine. but just today it started blinking/flashing again, now it wont come back normal after hours of trying.

[Al_Dodge_Bundy]

I would start by checking if there are bad solder joints on the mainboard.

Especialy in the deflection cicruit (flyback etc.).

Grtz Mark