This circuit was obtained from the February 1992 Radio Electronics magazine. In it, a bar of 4 LEDs flashes continuously at a speed given by C1 and the setting of R3.
The resistors in this circuit marked with * must be within 1% tolerance. The circuit is from the...
This amplifier with very high input resistance has variable gain and must be powered by a...
This regulator is equivalent to 2 AA batteries providing a 5 V output voltage. The circuit is from...