This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. Any photo transistor can be used and the transistor can also be a BC558. The meter is an analog type with end of scale of 100 µA.
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This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. Any photo transistor can be used and the transistor can also be a BC558. The meter is an analog type with end of scale of 100 µA.