This circuit was found in a 1980s documentation. The diodes may be general purpose diodes such as 1N34 or 1N60 and the indicator may be the lowest current range of a multimeter.
We found this circuit in the February 1989 issue of Radio Electronics magazine. The selectors are...
This circuit, which generates a linear sawtooth signal, can be used in a frequency-band...
This Audio System circuit was found in 1965 documentation. It is a 50 ohm line circuit with 22 dB...