This low-noise, low-drift amplifier was found in a 90's EDN. It can be implemented with modern equivalent operational amplifiers. The font must be symmetrical.
This constant current circuit was found in the October 1993 Electronics Now magazine. The current can...
When the input of this circuit goes to high level, the LEDs start to flash alternately. The...
This circuit is from a 1978 operational amplifier manual. The power supply must be symmetrical, and the...