A lot of making goes on in this community these days, but sometimes you’ve just gotta do some old fashioned hacking. You might have grabbed an old Speak and Spell that you want to repurpose ...

Using eight digital inputs, this circuit simplifies decoding of the common membrane 4x4 keypad matrix and eliminates the traditional requirement of scanning rows or columns. Any X-Y switch matrix, ...

Using eight digital inputs, this circuit simplifies decoding of the common membrane 4x4 keypad matrix and eliminates the traditional requirement of scanning rows or columns. Any X-Y switch matrix, ...