Testing the photovoltaic effect with a transistor

When you expose the silicon die of a transistor to a light source a charge is produced. CircuitsDIY opened up a 2n3055 transistor and did some experimenting. With the help of a magnifying glass he was able to built up a charge of 0.65V and produce 42.2mA of current.

Most photovoltaic cells are made of silicon chip above which there resides a very thin layer of noble metal through which around 1% of photon particles enter the material and activates electron flow.

Here I’m showing how to make one simple solar panel using transistor.

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  1. This is quite an old technique actually. Back in the 60’s and 70’s they used to cut the tops of things like metal-can BC109’s (small signal transistors) in order to make them into photo transistors. Many years ago there was experiments with doing photovoltaic stuff with LED’s and it does work, though output was very low.

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