Diagnosing Screen Interference

摘要

When mysterious image jitter or color distortion appear on CRTs, in many cases, the technician is called upon to correct the problem. Frequently, the first step in correcting the problem is to swap out the monitor, but the problem persists. Apparently, the problem is not the monitor or even the video card. The technicians next try surge protectors and UPS units, in the belief that the source might be the quality of the power, but without success. Next, the electrical contractor checks the circuits and finds nothing wrong. The local power company is called in and does a power quality analysis. Everything is within specification and they conclude the problem is not the power. It must be somewhere else.