IBM 6734_HBO: 2sec to black

[Welchs101]

Re: IBM 6734_HBO: 2sec to black

thanks!

[alexanna]

Re: IBM 6734_HBO: 2sec to black

OK, that means it's not an sensing an open lamp, so that side can be ignored. Now try measuring the resistances of each transformer secondary. I've circled the pins.

PlainBill

Samsung 174v, Monitor appears to use a somewhat similar power supply.
This monitor uses the same BIT3105 controller and the same inverter transformers. There are some slight differences I notice.
I was experiencing a seconds to black problem ,but this was approximately 120 seconds, it took quite a while to show up.
An image was always visible with a bright light directed towards the LCD panel .I noticed that the backlight on signal stayed above 1.4 volts on pin # 14 on the BIT3105 controller when the back lights were on and when they turned off. Measuring the resistance of the inverter transformer secondary's two transformers measured 1.474 K Ohms and 1.257 K Ohms and two transformers measured .995K ohms and .998K ohms. I was lucky enough to have a spare parts board that I was able to salvage two transformers that measured real close to the .998 K ohm readings and it repaired the seconds to black problem.
I think what is interesting is the length of time the seconds to black problem took to present itself.
Al.

[killian6pk]

Re: IBM 6734_HBO: 2sec to black

OK, that means it's not an sensing an open lamp, so that side can be ignored. Now try measuring the resistances of each transformer secondary. I've circled the pins.

PlainBill

Do you measure these transformers with the power on or off?


Never mind figured it out. thanks