This is an improved circuit from the earlier version also found in the April 1972 Radio Electronics magazine. The power transistors must be provided with heat sinks.
This circuit was found in a 1963 magazine, but can still be easily assembled with some current...
This loop antenna was found in a 1990s documentation. The circuit includes a field strength meter. The...
This sensor uses a capacitive system that oscillates at 45 MHz with the empty glass tube. Its...