We found this circuit in the Texas Instruments optoelectronics manual. Field effect transistors can be BF245 and bipolar BC548. The sensor is a photodiode in the photo-generator mode.
This simple circuit is designed to charger AA or AAA Nicad batteries. Current can be changed...
The circuit shown in the figure is suggested by Texas Instruments in its Linear Circuits...
A touch of a sensor triggers this minute for a time determined by R4 and C3. Times can be between a...