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.
In the figure we have the diagram of an amplifier stage using transistor and a 6AQ5 valve. The...
Being able to operate with frequencies up to 100 kHz, this circuit was found in a 90’s...
This circuit immobilizes a car with an old ignition system with platinum switches. It was found in the...