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 circuit was found in an old Philips publication. The circuit supplies a voltage corresponding to 4.5 V...
This circuit allows fluorescent lamps to be powered up to 40 W from 12 V car batteries. The...
This instrument, based on a 555, measures frequencies up to 1 kHz, but its scale can be modified by...