When [Adam] found himself in need of a force meter, he didn’t want to shell out the cash for a high-end model. Instead, he realized he should be able to modify a simple and inexpensive kitchen scale to achieve the results he desired.
The kitchen scale [Adam] owned was using all through hole components on a double-sided PCB. He was able to easily identify all of the IC’s and find their datasheets online. After doing some research and probing around with a frequency counter, he realized that one of the IC’s was outputting a frequency who’s pulse width was directly proportional to the amount of weight placed on the scale. He knew he should be able to tap into that signal for his own purposes.
[Adam] created his own custom surface mount PCB, and used an ATMega8 to detect the change in pulse width. He then hooked up a Bluetooth module to transmit…
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