Found in Popular Electronics, this sophisticated short-wave receiver requires a lot of skill from an eventual assembler. The coils are commercial types of the time, used in commercial radios.
The circuit shown in the figure generates a rectangular signal whose frequency depends on C1. For...
This circuit suggested by Texas Instruments, operates with pulses, and is based on an operational...
This circuit captures, through a coil, the signals emitted by another coil under the mat connected to...