This is the most critical section. The 101V0 board likely uses a small PWM IC (often a Viper series or a generic 6-pin chip like OB2269/CR6842) to generate a low-voltage startup rail.

If you’ve landed on this page, you are likely holding a broken bench power supply and staring at a specific model number: .

: Often the best source for high-quality photos of the board, which can be used for "visual tracing" of the circuit paths. Cautionary Note

If you are reading this, you likely have a dusty Wannien 101v0 bench power supply sitting on your workbench—either non-functional or in the middle of a repair project. Alternatively, you might be a hobbyist looking to reverse-engineer this classic, budget-friendly linear power supply for a custom build.

If the main switching transistor (e.g., 2SK3568, 7N60) shorts, it usually takes out the current-sensing resistor and the PWM IC. Replace all three.

If you’ve landed on this page, chances are you are staring at a faulty Wannien 101V0 power supply. Whether it’s a dead LCD monitor, a non-responsive CCTV power box, or an industrial display unit, the Wannien 101V0 is a common yet elusive piece of hardware. The golden ticket to repairing it is, of course, the . And you want it for free.

While you cannot get a branded "Wannien" official PDF for free (unless a previous owner scanned it and uploaded it to a forum), you can get the functional equivalent for free. The laws of physics are open source.