Building
on top of the logic
probe and expanding its functionality, next feature to add is frequency
counter. Logic detection by the LM339 had been replaced by very inexpensive
microcontroller.
Additionally resistor divider measures voltage on the input
Case / 3d files
The case for the probe is identical to logic
probe with small alteration to the LCD display opening as its dimensions are
slightly larger and inner rim had been altered to bring the LCD closer
outward.
Versions of the boards are available on our
Tindie store
Documents
Schematic
PCB (easyEDA)
Source code
3D Top STL file (LCD)
3D Bottom STL file