Logic Probe

To build any digital electronics project, you need a logic probe to test the state of your circuit, and while a multimeter will certainly work in it's place, a logic probe makes things so much easier. This logic probe was a simple construction of a 74LS00 wired as 4 inverters, for buffering the signal, two Light Emitting Diodes and I later added a small Piezo Speaker so I could test the square wave generator I was building for my Hex Display project.
Green Indicates High or 5 Volts, Red Indicates Low or Ground, both lights being on indicates Oscillation, which can also be heard as an audio tone through the speaker.

As you can see, I finally got around to posting schematics.

Pictures and Schematics

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