I got this Samsung 214t that I re-capped (PANASONIC caps) the power supply/inverter board in 2009. The monitor comes on with lots of strange pattern on the screens. The caps still check out good, the 13V feeding the logic board is good at 13V. There are many regulators and buck converter power supply on board. The output of the regulators (they are not 1117 series) are within 2~3%.
There are many SMD Electrolytic caps on the board that will need to be checked. I do not have the scope with me so I set my FLUKE to frequency mode and start testing to see if I can see any frequency reading on the caps.
Two of the caps has about 52KHz reading, 1 has about 150Hz, two has variable frequency between 25~85Hz. All other caps show 0Hz.
I replace those 5 caps, check the frequency, and they are showing 0Hz, now I get good pictures on the screen. Gave the monitor back to the happy customer. I will wait and see if I will get to see this monitor so I can check the caps I put in and see how long they will last. I could have start by jumping the cap to see which one will bring back the pictures but using the meter to pin point which one is more fun. I use my Fluke in AC mode and Frequency mode a lot for locating AC ripple in the power supply circuits.
There are many SMD Electrolytic caps on the board that will need to be checked. I do not have the scope with me so I set my FLUKE to frequency mode and start testing to see if I can see any frequency reading on the caps.
Two of the caps has about 52KHz reading, 1 has about 150Hz, two has variable frequency between 25~85Hz. All other caps show 0Hz.
I replace those 5 caps, check the frequency, and they are showing 0Hz, now I get good pictures on the screen. Gave the monitor back to the happy customer. I will wait and see if I will get to see this monitor so I can check the caps I put in and see how long they will last. I could have start by jumping the cap to see which one will bring back the pictures but using the meter to pin point which one is more fun. I use my Fluke in AC mode and Frequency mode a lot for locating AC ripple in the power supply circuits.
Attached Files
But today, I’m making an exception here. Why? No idea. Perhaps only because the repair details are still “fresh” in my head… which is ironic, given this is a 16 year old monitor that hardly anyone will care about today. It is new to me, though. 
I picked it up last November from someone on my local Craigslist. It wasn’t very close to where I live, but was close to a family friend that I had to go visit anyways. So after watching the posting on Craigslist for a few weeks and seeing it getting...
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