This circuit is from a 1978 Texas Instruments optoelectronics manual. The trimpot adjusts the LED current. Other currents can be adjusted if they are within the capacity of the FET.
This circuit provides a signal that is twice the frequency of the input signal. The circuit was...
This unusual amplifier configuration is from 1986. The circuit has a high resting current given the...
This circuit is from an 80's American documentation. The circuit uses components of the time which...