Hi
Can anyone help with schematics of power board for above Monitor.
I have got schematics for X233H but this X233H b is completely different.
Uses a TL494 IC.

The problem is,the two fluorescents only briefly light twice.

Many thanks

Meat Plow wrote:
On Wed, 14 Apr 2010 11:25:23 +0100, T Marshall
wrote:

Hi
Can anyone help with schematics of power board for above Monitor.
I have got schematics for X233H but this X233H b is completely different.
Uses a TL494 IC.

The problem is,the two fluorescents only briefly light twice.

Many thanks

I would be looking more at the inverter or maybe one of the
fluorescent's being bad than the PSU unless you've verified
the PSU is bonked somehow.
thanks for reply. Its the inverter and control section I am trying to
check. Every thing else seems to be ok. It did fire up once and display
picture OK. looking for circuit to see if I can inhibit error detection
Tommy

On Wed, 14 Apr 2010 14:57:36 +0100, T Marshall
wrote:

Meat Plow wrote:
On Wed, 14 Apr 2010 11:25:23 +0100, T Marshall
wrote:

Hi
Can anyone help with schematics of power board for above Monitor.
I have got schematics for X233H but this X233H b is completely different.
Uses a TL494 IC.

The problem is,the two fluorescents only briefly light twice.

Many thanks

I would be looking more at the inverter or maybe one of the
fluorescent's being bad than the PSU unless you've verified
the PSU is bonked somehow.
thanks for reply. Its the inverter and control section I am trying to
check. Every thing else seems to be ok. It did fire up once and display
picture OK. looking for circuit to see if I can inhibit error detection

The main switcher and the inverter monitoring are totally separate on
every LCD monitor I have worked on. The backlights are fired at full
brightness, then the current feedback circuit kicks in to achieve the
preset level. If the monitoring chip detects an imbalance between the
2 (3) tube drivers it shuts them down.

Best suggestion: get onto badcaps.net and usually someone there will
steer you through this. Circuits are rarely required.