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5V AC/DC Converter Switch Power Supply Module 3W 700mA Industrial Voltage Regulators
Following on from playing with the Hi-link HLK-PM01 I got this generic even cheaper board from Ben Dooks, after carefully wiring it up, I shoved it on the Kikusui TOS 8650 Withstand Voltage Tester: https://youtu.be/6ryuo0JYQsQ This shows the cheap chinese powersupply breaking just below 2 kVac
Skippy