7" low-EMF tablet

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7" low-EMF tablet

Karl
I recently bought a tiny board and LCD:

https://www.sparkfun.com/products/12857
https://www.sparkfun.com/products/12086

What's nice about these is that they don't have many parts that emit electromagnetic radiation, and the ones that do run at frequencies that are easy to shield. Right now I'm running it in a makeshift enclosure made out of a cardboard box coated with radio-absorbent paint, with the AC adapter on the other end of a 25' extension cable, and it's the first time that I've enjoyed using a computer. The drawbacks are that the CPU is really slow, the  screen's color depth is terrible, and it only runs Android or Linux, but I still like it better than my Thinkpad.

The next step will be to build a better case. I can easily share plans when I'm done if anyone's interested.
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Re: 7" low-EMF tablet

earthworm
It sounds interesting but shielding the front-side effectively while remaining transparent is still not going to be easy.
Perhaps it's an idea to cover the blue surface around the connectors facing the computer at the back of the panel with a thick plate of aluminium to further reduce the already limited emf-exposure.
This would work only in case the fields emitting from the panel ( which then will be reflected in the wrong direction ) are much less than those from the computer.
You could of course also use the same absorbent paint, but this may re-emit as soon as it is filled up and starts to spill over, at least some people seem to have had unpleasant experiences with this type of shielding material.
To move the computer away by means of a long shielded cable is possibly another option.
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Re: 7" low-EMF tablet

Karl
The good news in this case is that the LCD is in a metal housing that wraps around behind it, so only the power to the LED backlight and the wires that control the individual pixels are un-shielded. I'm pretty sure the backlight runs on DC.
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Re: 7" low-EMF tablet

Karl
You can see the metal behind the orange ribbon connector in this pic:

https://cdn.sparkfun.com//assets/parts/8/7/1/8/12086-03.jpg

The blue surface is the circuit board for the LCD.