This circuit is from an old English publication from 1968. We can implement it with TIP32 transistors in a more modern version. Power can be done with either large batteries or a power supply.
This circuit was published in an English magazine from 1977, but it can be easily assembled since...
The maximum current of this circuit is 1 A. The circuit is from Motorola Linear Interface ICs from...
This circuit is a handset receiver that picks up the signal emitted by a coil under the rug or...