This circuit with transistors of the time was found in the November 1972 Radio Electronics magazine. The circuit also generates a sawtooth signal for use on an oscilloscope.
This circuit was found in an American documentation from the 80's. The components are from that...
The circuit shown is from the Texas Instruments optoelectronics manual. It is intended for audio...
This circuit drive an LED with constant current determined by the values of the resistors of 10...