New Ultrasonic Sensor Board


Senior Member
Just got some test boards for our old friend the HC SR04 ultrasonic rangefinder sensors. These sensors have always been a conspicuous bargain at just $1 but now down to just 65 cents, the ONLY thing cheaper since Covid. They interface easily to a Picaxe using the ULTRA command after doing the clever and well-documented one-pin mod here in the forum.

This standalone test board plus sensor costs just $2.41 at No mods required, it bypasses the Picaxe and provides a direct LED readout in CM of the distance measured, plus it sends a continuous 9600 baud serial data stream of distance measured.

Tech info at

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Senior Member
A real low-tech answer to a problem. Fastening one of these guys near the body of the robots forklift so we can see how close to the load we are. And monitor the output using the overhead camera 😂