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.
This isolated shield is from an old documentation, making use of an operational one of the time. It...
We found this transmitter circuit in a 1990s spy book. The coil data is provided along with the...
In this circuit we have the way to use common diodes to obtain low regulated voltages in a single...