greetings
so a few days ago I wanted to turn on my Viewsonic VP191s LCD display but it would not, not even the power led would light up. So I took it apart, looked for burned caps but found none. Next I took out the PSU and checked the output voltage: When turned on there is a faint clicking sound coming from the PSU, ca. 3/5 per sec, the voltage fluctuates between 12.1 and 12.3 V.
If I add a load, a 12V 5W bulb,
either of the following happens:
1) the voltage drops instantly, the bulb does not light up, and the clicking sound speeds up, about twice as fast, or
2) the bulb lights up and the output voltage stabilizes at 12.3V.
I have only tested the PSU for less than a minute.
Now I'm not sure what to check for next, any ideas?
thanks
so a few days ago I wanted to turn on my Viewsonic VP191s LCD display but it would not, not even the power led would light up. So I took it apart, looked for burned caps but found none. Next I took out the PSU and checked the output voltage: When turned on there is a faint clicking sound coming from the PSU, ca. 3/5 per sec, the voltage fluctuates between 12.1 and 12.3 V.
If I add a load, a 12V 5W bulb,
either of the following happens:
1) the voltage drops instantly, the bulb does not light up, and the clicking sound speeds up, about twice as fast, or
2) the bulb lights up and the output voltage stabilizes at 12.3V.
I have only tested the PSU for less than a minute.
Now I'm not sure what to check for next, any ideas?
thanks
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