VGA Testers for the Children

Recently on our Hack A Day forums a member asked about getting some VGA testers made in our “Request and Commissions” forum for a charity called the World Computer Exchange, who take old office PC’s and freshens them up to be used by children in developing countries for their education.

I sort of wanted to do a no brainier electronics build as I had been working on that Apple II weather display for quite a while at that point. I say no brainier because I decided to use one of the many already designed vga testers out there and all I really had to do was get it to fit in whatever box we ended up with.

I choose the deogen because it was already featured on Hack A Day, supports multiple raster patterns and resolutions (640×480 through 1280×1024), is already pretty darn small, and uses an ATTiny 2313 which is good because I am already set up for AVR micro controllers. For a case I choose to use some plastic “Ice Breakers” mint boxes, which due to their oval shape makes it quite a bit smaller than an altoids tin. The challenge is on to shove a PCB, switch, 9V battery, 2 buttons and a vga connector in the cramped space.

Join us after the break for a pile of pictures and some build notes.

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LCD: Replacing CCFL with LEDs

[Fileark] had the backlight on his digital picture frame go out one day. These are generally Cold Cathode Fluorescent Lamps which require an inverter to source the voltage necessary for proper operation. When they stop working, the inverter is usually to blame. Since that circuit is made up of pretty small surface mount circuitry, he decided to replace the backlight with LEDs rather than repair the inverter.

In the video after the break [Fileark] will walk through the entire project. After snooping around inside the picture frame he sizes up a strip of LEDs on a flexible substrate. The metal retaining bracket that hosts the LCD must be altered to fit the new light source and for that, he’s included a hacking montage in his video. The final result looks stock and he estimates the screen is around 97% as bright as with the original backlight.

This isn’t the first time we’ve seen an LED edge-lit upgrade. The last one we saw even used a custom PCB to host the LEDs.

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