Found in a 1966 publication, this circuit is a simple version of a field strength meter. The diode is a general-purpose germanium type.
This 800 Hz sinusoidal oscillator was found in a 1970s American documentation. The transistor...
Similar metronome settings can be found at several points in this section. This was taken from a...
Pressing S1 by a moment L1 glows up, remaining by a time interval depending on C1. This time...