Charles Wenzel

The induction receiver shown below in Figure 1 is very sensitive and can serve a variety of purposes. It is excellent for tracing wiring behind walls, receiving audio from an induction transmitter, hearing lightning and other electric discharges, and monitoring a telephone or...

Here's a general-purpose 2 watt audio amplifier with excellent overall performance. It is easily configured to serve as an audio output stage for lower power applications or as a more powerful amplifier for room-filling volume. I've even tried it as an electric...

This little gadget uses a small 3 volt solar cell to charge a 6 volt NiCad battery pack which, in turn, may be used to charge many models of cell phones and other portable devices. The circuit "scavenges" energy from the solar cell by keeping it loaded near 1.5...