When my Radio Shack logic probe gave up the ghost a while back, I took it apart only to discover that the probe consisted of two piggy-backed printed circuit boards and an estimated 20-30 parts. It was time for a new logic probe, so I went shopping for a new one. I did find one or two products but they seemed much more expensive than my original logic probe. It was a fortunate turn of events that I came across the Mondo Technology web site. Luhan had developed a logic probe that required the minimum of components. What’s more, he added 15 other functions as well!
- Logic Probe with pulse detection
- Logic pulse generator
- Event counter
- 0-5 volt voltmeter (measurements are about 2% high, though)
- Diode junction tester
- Capacitance meter
- Inductance meter
- Serial ASCII generator
- Square wave signal generator
- 500 Hz signal generator
- White noise generator
- Pulse Width Modulation signal generator
- 38 KHz IR LED signal generator
- MIDI note generator
- NTSC video pattern generator
- R/C Server tester
Luhan has packed a lot of functionality into this project, which uses a PIC 16F870 and a handful of other parts. I built the project on a piece of project board and replaced the original circuit board with my new one, all for a cost of less than $10. Although some of the functions won’t replace dedicated devices, it is nice to have so much functionality in one small package. For complete details go to the SuperProbe project on Luhan’s site.
Luhan uses his own assembler for his project, so I translated his source into MPASM. The MPASM SuperProbe source and resulting HEX file can be downloaded from our site.