Desktop photo of the HP545A logic probe connected to an Arduino UNO digital output. The UNO logic state is low, and the logic probe light is OFF.
Desktop photo of the HP545A logic probe connected to an Arduino UNO digital output pin. The logic state is HIGH and the 545A probe tip light is ON. It works! A second HP545A probe can be seen in the photo along the top edge.
Screen grab from the HP545A manual showing how the probe responds to various inputs (ground, floating, high, pulsing high, etc.).
Random Garage Box Find: HP 545A Logic Probes (Vintage). Verified 2 HP545A logic probes are both working (although have only one complete probe tip - second is broken off). Being from the mid-70’s, not surprised that they use a small light bulb for the main […]
[Original post on mastodon.radio]
