This circuit controls 6 LEDs in two sets with the phase change cycles controlled by a 555 oscillator. The circuit can be powered by voltages between 6 and 12 V.
To operate in a harmonic of the crystal frequency, tuned to a trimmer in the resonant circuit of...
This amplifier for recording heads was found in a Radio Electronics from September 1963. The...
This circuit is from the 1983 Intersil Databook. The circuit operates on 5 V power and has a...