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Main => Monitor/Video Forum => Topic started by: ahofle on August 28, 2014, 12:38:14 am

Title: Help -- LCD monitor going out!
Post by: ahofle on August 28, 2014, 12:38:14 am
I have an old 20" 4x3 Samsung SyncMaster 204T that I use for web surfing that seems to be dying.  The symptoms are very strange to me, but hopefully someone will recognize them.  Over the last couple weeks, whenever I turn on the computer, the monitor wakes up and I see windows boot up.  The screen at this point is a bit dim and flickery and after a few more seconds goes completely blank.  If I turn the monitor off and back on, the screen appears for a second and then goes back to a black screen.  Same if I switch inputs...I see the screen briefly and then black.
After several minutes of switching inputs between analog and digital, powering on and off, suddenly the monitor comes on in its full bright glory and is perfectly fine for as long as I keep it the computer on and the monitor synched.  The next day when I turn it on I have to repeat this.
I have eliminated the video card (does the same thing on another computer) and cables (even the VGA input with a different cable does the same thing) as culprits. 
Does anyone have an idea what the problem is and if it's something that can be serviced by a novice/intermediate solder gun user?  I'd rather not toss this rare 4x3 gem into the trash if I can fix it.
Title: Re: Help -- LCD monitor going out!
Post by: Vigo on August 28, 2014, 12:57:21 am
I am far from a monitor expert, but it sounds to me like the CCFL tube or power inverter is going out. My understanding is this is pretty much like a ballast on a fluorescent light. It pumps out a high jolt of power to light up the ccfl tube to light it, Older tubes don't turn on like they should right away, and the inverter no longer attempts to jolt it after a few seconds.

I have fixed a monitor with this issue, and it pretty much involved decasing the monitor, sliding in a new after market ccfl tubes on the top and bottom of the lcd panel, and wiring it to the inverter if the inverter is still good. Not too hard, but if the inverter is going out, you can always just externally wire up a second inverter to your monitor. I just used a inverter that plugs into a psu and never even bothered wiring it directly into the monitor, just had another wire going to the computer.

Also, don't worry if the tube size is an inch or so shorter than your old one. They charge a lot more for monitor precise sizes, and a shorter tube lights up just fine.

Oh, and I learned the hard way that ccfl tubes are very fragile. Don't bend. And don't touch the end of the tube either. Youch!
Title: Re: Help -- LCD monitor going out!
Post by: JDFan on August 28, 2014, 09:19:15 am
Another option - for less or the same as it is going to cost to try and fix it you could buy a refurbished one from Arrowdirect (using code "slickmon" for 50% off) they have several 4:3 20" monitors to choose from and new stock always coming in for example they currently have a similar 20" 1600x1200 syncmaster 204b for $40 shipped (Tax varies depending on where you live they may\may not charge it but shipping is always $8.99 using Fedex ground) and then you would have the parts needed to fix your or could just use the refurbished unit.
Title: Re: Help -- LCD monitor going out!
Post by: Generic Eric on August 28, 2014, 10:18:01 am
So...I had an LCD do that.  Worse part was I only had used it twice in the time I bought it.  Looking back that is probably why it was such a low starting price on ebay.  Anyway.  Here is the second third of my story.

I looked up the model number on ebay and found a cap kit.  The listing for the cap kit said it repairs a majority of problems.  I bought the cap kit.  Its on the shelf next to the still intact monitor.

If the cap kit does fix it, happy days.  If not, atleast it will be a bit of applied soldering practice. 

Watch for a thread detailing the exciting conclusion!
Title: Re: Help -- LCD monitor going out!
Post by: Sarver Systems on August 28, 2014, 12:51:07 pm
I think its the CCFL invertor as well. THey are notorious for burning up.

The newer monitors use LEDs and don't have an invertor.

The invertor takes a low DC Voltage and turns it into a High AC voltage for the bulbs to operate.

A cap kit will not fix the CCFL issue, but since you've already bought it, its still worth a try!
Title: Re: Help -- LCD monitor going out!
Post by: ahofle on August 29, 2014, 12:10:52 am
Thanks guys...sounds like it may not be worth it to attempt a repair given that I may be able to pick up another for $40 shipped, although I may open it up just for fun to have a look.
And thanks alot to whomever snatched up that 4x3 syncmaster on the site JDFan posted!  :angry:   ;D
Title: Re: Help -- LCD monitor going out!
Post by: JDFan on August 29, 2014, 12:21:12 am
Thanks guys...sounds like it may not be worth it to attempt a repair given that I may be able to pick up another for $40 shipped, although I may open it up just for fun to have a look.
And thanks alot to whomever snatched up that 4x3 syncmaster on the site JDFan posted!  :angry:   ;D

Shows they still have one according to my list -- http://arrowdirect.com/samsung-syncmaster-204b-20.html (http://arrowdirect.com/samsung-syncmaster-204b-20.html)  (they also get new stock every day or so so if they sell it just keep checking back !)
Title: Re: Help -- LCD monitor going out!
Post by: ahofle on August 29, 2014, 12:42:13 am
Sure enough there it is...no idea how I missed it.
Anyway, for fun I opened up the monitor and found the power board...the caps are indeed a bit bulged.  Then I found this on Amazon which matches exactly the board in my monitor:
http://www.amazon.com/Repair-Samsung-Monitor-Capacitors-Entire/dp/B007JBUF9O (http://www.amazon.com/Repair-Samsung-Monitor-Capacitors-Entire/dp/B007JBUF9O)
Sounds like the exact symptoms...not sure if 6 capacitors are worth $13, but I may give it a shot because I don't have time to hunt them all down.
Title: Re: Help -- LCD monitor going out!
Post by: ahofle on September 06, 2014, 12:12:16 pm
Just wanted to update this thread...I ordered the capacitors in the link above and installed all 6 of them on the power board.  Fired up the monitor and it's perfect again!  Thanks for the replies everyone.
Title: Re: Help -- LCD monitor going out!
Post by: Generic Eric on September 06, 2014, 02:22:19 pm
Glad to know this worked for you!