LCD Moniter taking 5-10 mins to display

[CraiGDaniel]

So my beloved Syncmaster 226BW is finally giving up the chase i think. Had this monitor for 5> years, most outstanding bit of tech i've owned. An award winner of it's time.

From a cold turn on it's just switching in and out of signal for up to 10 mins. The blue light on the button will flash on and off, and the monitor makes a horrible whining sound.

After quite some time it will eventually make a more horrible whining sound, and the picture slowly fades in at which time it settles down and is back to itself. If i turn it off for 5 mins and turn it back on, it comes back instantly.

However leave it for a while and i'll have to wait again. Also to note is a whining noise coming off the monitor when its just turned off, without the computer even turned on.


Now monitors repair is not my game, however i may be willing to try as it sounds like a dead capacitator to me? Anyone out there clued up on these things? Really don't wanna get rid of my baby.

 

[coffee]

So my beloved Syncmaster 226BW is finally giving up the chase i think. Had this monitor for 5> years, most outstanding bit of tech i've owned. An award winner of it's time.

From a cold turn on it's just switching in and out of signal for up to 10 mins. The blue light on the button will flash on and off, and the monitor makes a horrible whining sound.

After quite some time it will eventually make a more horrible whining sound, and the picture slowly fades in at which time it settles down and is back to itself. If i turn it off for 5 mins and turn it back on, it comes back instantly.

However leave it for a while and i'll have to wait again. Also to note is a whining noise coming off the monitor when its just turned off, without the computer even turned on.


Now monitors repair is not my game, however i may be willing to try as it sounds like a dead capacitator to me? Anyone out there clued up on these things? Really don't wanna get rid of my baby.

Your looking at the rectifier that is bad. This is basically a transformer type component that has developed a short in its windings. Replacing them is really not an option because of cost. I went thru a bunch of bad HP highend monitors with this problem years ago. Its gonna wine and squeel alot.

Time to retire the monitor and look into a new one.

 

[CraiGDaniel]

Not good news then.

The rectifier wouldn't be this component would it?

http://www.ebay.com/itm/TM-12260-In...688?pt=LH_DefaultDomain_0&hash=item1c25e233d8

 

[coffee]

Not good news then.

The rectifier wouldn't be this component would it?

http://www.ebay.com/itm/TM-12260-In...688?pt=LH_DefaultDomain_0&hash=item1c25e233d8

When you look at the back of the TV tube, There is a rubber suction type deal on the side. This goes down to the rectifier that supplies the current. There is an adjuster on the rectifier but adjusting it will do no good.

Its done.

 

[phaZed]

Your looking at the rectifier that is bad. This is basically a transformer type component that has developed a short in its windings. Replacing them is really not an option because of cost. I went thru a bunch of bad HP highend monitors with this problem years ago. Its gonna wine and squeel alot.

Time to retire the monitor and look into a new one.

I don't think he's looking at a bad rectifier. Rectifiers don't make noise unless they are popping. A rectifier can be a Half-bridge, or full bridge rectifier and consists of 4 diodes placed end to end with leads coming off:

The purpose of the rectifier is to convert AC to DC power. The diodes limit current in one direction, so in this 4-diode configuration (and with a full-bridge rectifier) the Diodes make sure that positive(+) and negative(-) do not alternate (AC) at any given time, on both sides of the sine wave.

The output DC is then usually fed into a series of capacitors (Usually the biggest ones there), resistors, and coils/chokes.

Rectifiers USUALLY are packaged like this:

OR

I have never heard diodes making noise, in an IC package or individually, but it is quite common for Capacitors to make high pitched squealing noises which is the sound of it charging/discharging at a high frequency.. and failing, incidentally.

Definitely check out the capacitors... you will be looking at the ones on the AC (Supply side) of the power supply. They are usually close to the Bridge rectifier, and the biggest ones in size, physically. If your looking PAST the transformer, then you have gone too far...

AC(Line In)-->Fuse-->Rectifier-->chokes/coils, caps, resistors, protection diodes-->Transformer----- === Filtered DC to control boards/processor.

 

[phaZed]

When you look at the back of the TV tube, There is a rubber suction type deal on the side. This goes down to the rectifier that supplies the current. There is an adjuster on the rectifier but adjusting it will do no good.

Its done.

He has an LCD, not a CRT (Cathode Ray Tube). So this would not apply. It's not the rectifier that connects to the tube or that you adjust on tube TV's, it's the Fly-back transformer which creates the necessary voltage to allow the tube to "shoot" the RGB phosphors with electrons and light up the screen.

 

[Larry Sabo]

I would put my money on it being bad caps. "Rectifiers" (diodes) once shorted, don't usually work again if left for a time. Squealing is common when caps go bad or a switch mode power supply is overloaded. Shorting SMPS transformers is a common problem, too, and the only way to test them is with a "ring tester" or by replacing them. Measuring them with an ohm meter will show them as shorted, even when they are not. If it were mine, I'd open it up and look for swollen caps. If none found, go ahead and try replacing the transformer(s), given the low price. Also, use a magnifier to carefully inspect the solder joints for cold joints. They are easily repaired at no cost.

 

[coffee]

Thought he had a crt?? I might have gotten the name of the part wrong but its the transformer dealy that hooks to the side of the tube. I have had them make all kinds of noises.

Since this is a LCD then yes, I would go with a bad cap. Either dried out or defective.

 

[14049752]

Yeah, adding my vote for bad caps. That was my initial thought, then I read coffee's post.....had to go back to make sure I read "LCD" and not "CRT"...

Take it apart, replacing the bulging/leaking caps. If it works again, awesome. If not, you only put a couple of dollars into trying.

 

[altrenda]

Both monitors on my desk were rescued from similar problems. Clients thought it was a good time to get newer, bigger ones.

Both had bad caps in the power supply section. Spent more time taking them apart and putting them back together than it took to remove and solder in new caps.

My experience with these led to some good business replacing caps on monitors, Mac power supplies, and a couple Vizio TV's.