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[email protected] swohlfarth@gmail.com is offline
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Default Viewsonic 15 inch LCD hard to turn on

Steve,
I built my own ESR meter using a function generator and a fluke DMM. I
set the generator to 10kHz and about 10V RMS. I then placed a 10k
resistor in series with the output so it will be sourcing 1mA RMS. Take
the other end of the resistor and the ground from the function
generator and connect these to your DMM on the AC mV range. The meter
should read overrange. Connect a 10 ohm resistor across the points and
adjust the output of the function generator until the meter reads 10
mV. Now your ESR meter is calibrated. Connect the two points across
various caps in the circuit. If you find any that read more than a
couple mV (Ohms), they are most likely bad. Note, a 1uF cap at 10kHz
should read 15.9 ohms, a 10uF should read 1.59 ohms and so on.
Scott

wrote:
wrote:
I recently fixed a VS 17" LCD monitor and found a number of bad SMD
electrolytic caps in the power supply. You can usually spot them
leaking on the PCB. Replace those first and see if it works better.
Scott


I didn't see anything obviously leaking or smell the typical fishy
smell.

Looks like I need to build an ESR meter.

Thanks,
Steve Greenfield