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+--- Thread: Wavy screen of my System-80 fixed (/thread-994.html)
Wavy screen of my System-80 fixed - ChickenMan - 21-02-2026
Well I finally fixed my System-80's wavy screen. The Tech manual says to fix this problem, replace the large 22,000uF electrolytic and the 2 large IN5408 diodes.
So replaced the power supply large 22,000uF cap with a 35v 105oC one (original was 16v and 80oC) but with the connectors on the one end. I connected the + terminal okay but run a wire around to the -'ve pcb connection and used hot melt to keep it all in place. Replaced the 2 large IN5408 diodes, appears they had been previously replaced but soldering was crap with the solder pads lifted off the PCB. Its a wonder it worked before. I also replaced the grey 240v power lead with another grey power lead so it doesnt react with plastic case. Put it back together after checking the power supply voltages. Then connected a monitor, turned it on and bingo, stable as a rock. Stayed that way for 15 min. as it would be wavy right from the start in the past. A good afternoon job I've been putting off.