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Main => Monitor/Video Forum => Topic started by: menace on February 03, 2005, 07:43:29 am

Title: How to test transistors on neckboard?
Post by: menace on February 03, 2005, 07:43:29 am

the ones that control the color drives?  are they standard transistors --i.e. base emitter collector or are they a different type?

Title: Re: How to test transistors on neckboard?
Post by: menace on February 03, 2005, 08:35:47 am

NM
http://www.kilowattclassroom.com/Archive/AN0007.pdf

it was an npn type

Title: Re: How to test transistors on neckboard?
Post by: ChadTower on February 03, 2005, 09:43:50 am

Take them out of circuit, test with DMM, put back or replace.

Title: Re: How to test transistors on neckboard?
Post by: Ken Layton on February 03, 2005, 10:15:02 am

Yes they are conventional high voltage transistors. If you suspect a particular transistor driving a particular color is bad you can swap it to a different color driver. For instance, if you think the red driver is bad move it to the green or blue  instead to see if the problem follows that particular transistor. Sometimes these will test good with a meter but break down under operating voltage. Over my many years of monitor repair I think I've only had to replace a handfull of color driver transistors.