Samsung 305T slightly different problem

[jimthompson]

Hi,

First I'd like to say, what a great site! I am the kind of person that hates it when a favourite piece of electronics dies, leaving no option but to toss it in the trash...what a waste.

I'm hoping that "bad caps" is the answer to my recent problem with my Samsung 305T monitor. I've had it about 4 years now, and about a year ago I had the common flickering problem. That has since been fixed by modifying the signal board with heat sinks and a small fan. All has been good until a couple days ago when the monitor was coming back on from power saver mode. The screen came on for a split second and then went off again, on-off, on-off, continuously. The on-off continued for about 10sec and then the monitor came on and stayed on, remaining on for several hours. Then later that day the monitor started doing again from the on condition and never stopped flashing on-off so I switched it off. Turning the monitor off and on did not fix the problem. I did notice that the area around the power supply board was very hot, almost too hot to touch. After reading online about bad caps on the power supply board I disassembled the monitor and inspected the the PS board. I found a variety of Rubycon and CapXon capacitors, but none show signs of bulging.

Does my problem sound like bad caps? Do I not see any bulging because the caps are only just starting to fail? Any advice would be greatly appreciated.

Best Regards,

Jim Thompson

[budm]

Re: Samsung 305T slightly different problem

Bad caps can look normal, you need to check its ESR and capacitance value with cap meter that can read capacitance and ESR, or you can throw in a set of new caps which should be done anyway.

[retiredcaps]

Re: Samsung 305T slightly different problem

I did notice that the area around the power supply board was very hot, almost too hot to touch.

Caps die from heat. Caps can be dried out and not bulge.

Capxon makes terrible quality caps.

[jimthompson]

Re: Samsung 305T slightly different problem

Thank you for the responses. I think I will go ahead and order replacement caps. In the meantime I will have look at improving the convective cooling in that area of the monitor. It is designed presently to cool by natural convection, but there is a lot of blockage to air flow. I'm guessing though that I'll need to leave a cage of metal around the PS board to minimize EM interference with nearby electronics.

Regards,

Jim Thompson