This speaker overload protection circuit was found in Radio Electronics from the 1980s. The circuit uses a 9 V relay but can be powered by 12 V for a relay of this voltage.
This is one of the first radios with an integrated circuit. The circuit is from a Radio...
This circuit already incorporates the amplification stage, since the oscillator is of the type of...
Output stages driving relays or other loads are plugged to the outputs of a 4017. The trigger...