Only 3 years old, LED blinking and relay clicking on and off. The "on/off" switch short circuits the mains SMPS side of the opto isolator to switch "off" the monitor, bit unusual. Disabled the line output drive and running from 50 percent mains and same clicking/ticking. Stable 7V or so on the driver side of the opto-isolator and a 7805 gives a stable 5V for the micro area. PS Ds and Cs seem ok Any ideas where to look other than tracing back from the relay, LED area and back to the PS rails.
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