This circuit produces sounds of 6 different notes depending on the keys activated. The circuit is from a Radio Electronics from May 1965. The transistor must be equipped with a heat radiator.
This circuit uses a common diode to switch a high frequency signal. The circuit was found in the...
This circuit was found in a 1974 publication. It converts the applied voltage into pulses of...
Based on TTL logic this circuit can vary both the frequency and the pulse width of a rectangular signal....