
Optical Input for Oscilloscopes
by: Kevin C. Carpenter, CBET
Here is a creative technique for capturing light signals on an oscilloscope. Simply solder a phototransistor into a BNC connector and then connect to the input of the oscilloscope. This device detects the light emitted and displays the corresponding waveform on your oscilloscope. Some care should be taken to select a phototransistor which is responsive to the wavelengths you wish to detect.
This device is useful in troubleshooting any device utilizing optical switching, interfacing, or communication. In fact, to make it even more useful connect it to the end of a BNC cable. This way, the unit can be positioned closer to the specific light source.
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This page was published on 9/18/98