¿ªÔÆÌåÓýOkay yes so that¡¯s a CCFL (cold cathode fluorescent) backlight. You will most likely find the backlight driver on a separate board (because of high voltage AND noise). CCFL initially goes up to a high ¡°strike¡± voltage, then after the tube conducts the voltage drops. And it¡¯s AC voltage, keep that in mind if you try to measure it. The CCFL driver may shut down if it detects that the tubes do not fire. But most likely that driver has fried. I guess make sure the driver has DC input power, and maybe look for AC voltage on the output when you apply power. It¡¯s not 60Hz, so keep that in mind. Your DMM may or may not give you an accurate reading. You can buy generic CCFL drivers but of course OEM is best if you can get it. Maybe Tek still sells it? If you need to use a generic driver, try to find someone on the group that knows what voltage you need. I don¡¯t know if there is much difference in CCFL voltages. Dan ? From: [email protected] <[email protected]> On Behalf Of Zack Widup via groups.io
Sent: Tuesday, April 16, 2024 2:19 PM To: [email protected] Subject: Re: [TekScopes2] DPO70804 ? Thanks. The backlight consists of two very small diameter glass tubes about 10 inches long and somewhere around 1/16 inch in diameter. There are two pink wires and one yellow wire coming out of that assembly and going to a plug on a board that appears to be a high-voltage power supply. The power supply board is even labeled "high voltage." I don't think that is an LED backlight. The pc board patterns going from a module on the power supply board are covered with epoxy up to the connector. I cannot figure out a way to measure the voltages out of the connector to the pink and yellow wires without cutting the wires. ? Zack ? On Tue, Apr 16, 2024 at 1:45?PM dan.meeks222@... via <dan.meeks222=[email protected]> wrote:
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