Any Monitor repair techs around? got a problem

[BarnyardMonkey]

Hopefully someone can give me an answer on my monitor that went bad.

it worked fine for quite awhile,then every now and then i would hear a light pop noise and the monitor screen would sorta flash.
then everything would be fine after that.

so,a few days later i turned it on and got nothing.
just the power light.

Its a "Gateway 19" EV900".
i hear they have alot of problems.

I searched around and came across a page that listed a few Resistors that may have went bad.
so i checked them out but for some reason there is 2 Resistors that won't read the right voltages when soldered in the board.

R573 should read 68K,but it reads 15K.
but after taking it out of the board it reads the right voltage which is 68K.

And there is also one other that does the exact same thing.
but its one of the turn knobs closest to the FBT.
should be 20K,but reads 10K in the board,and 20K out of the board.


Was hoping maybe someone that knows a bit about Repairing monitors could tell me what may be the prob with the false readings before i toss out the monitor.



Shawn.

 

[Workin']

Well the "problem" with the "false" resistance readings while the resistors are in-circuit is no problem at all - you are just reading the resistance of a different path rather than across the resistor. If they read correctly when isolated from the circuit then they are not defective.

My guess is that either the high-voltage power supply or the flyback transformer went bad. It might be fixable for under $100. Or might not be. Find a place that gives free estimates and see what they say.

 

[gosstech]

How old is the monitor? If its under 3 years you might be able to get gateway to replace it. I had the same problem with a KDS VS-195 and they replaced the monitor after I had it for 2 years.

 

[randypj]

A bloke here at work says "the popping that you heard was the EHT (extra high tension) cracking over inside the tube base. You probably have had the frequency in your monitor control pannel too high for your monitor (check the specs of your monitor).

It is a good possibility that the driver circuit for the EHT has gone bad (this is usually a heavy duty transistor suppied by an oscillator running at anywhere from 15,000khz upwards).

If you can get a circuit diagram, this can be desoldered from the circuit board and replaced. It normally sits next to the EHT transformer. You can trace to the EHT transformer by following the connection from the top of the monitor tube back to the circuit board.

CAUTION--DO NOT TOUCH THE CAP OR THE TUBE--A HIGH VOLTAGE CHARGE CAN REMAIN STORED IN THE PICTURE TUBE FOR SEVERAL WEEKS--BE CAREFUL NOT TO KNOCK THE PICTURE TUBE BASE.

He's a Brit.....I hope he knows what he's talking about.<GRIN> He talks a good game and used to repair TV's.

Hope this helps you.
--Randy