This is another LCD monitor modified for reducing the electromagnetic emissions. This particular monitor has a 21.5" 16:9 display but the screen resolution is 1920 x 1080, which is Full HD. The input is VGA or DVI. The backlight hasn't been replaced, it is still the original LED array of the manufacturer, but now it is powered with a filtered DC voltage generated by a linear power supply. The voltage applied to the LED strip is between 40 and 50 V DC. The LCD module hasn't been opened at all so it certainly has no problems. The mainboard is enclosed in a thick aluminum box and it is powered by a separate circuit of the linear power supply, at 5 V DC. In this case we have been able to maintain the original plastic frame of the monitor. From the back this monitor is a little different than the original one, as we have to make two apertures for the passage of the cables, however from the front the monitor looks exactly like the original product. We have also improved the power supply box by making it of steel, which is better for reducing the low frequency magnetic field of the transformer. The power supply is supposed to stay on the floor at some distance from the user, but anyway, with a steel enclosure there is less risk than another cable could pick up the magnetic field of the transformer.
The results for the reduction of the electromagnetic emissions are very good, and the brightness of the display is also quite high. The brightness can be adjusted completely, from very dim, to maximum bright, by means of a multi turn knob located on the power supply box. This monitor size is perfect for all office and design work, and also for watching videos and movies.
The power supply of this monitor provides also a separate 5V 2A exit and a separate 12V 0.75A exit, which can be used to power other devices on the desk. For example the 5V exit can be used to power the terminal of an optical DVI cable and a optical USB cable, while the 12V exit can power a speaker set or a LED desk lamp. For more information about this project contact us.