This circuit takes advantage of the noise generated at the reverse biased junction of a germanium diode. Other types of diodes can be used. The signal is weak.
We found this circuit in an old publication. The components used are rare today. Accuracy depends on...
This TTL circuit has a well-known configuration, having been found in a Radio Electronics magazine...
The circuit shown in the figure was suggested by National Semiconductor in its 1994 Linear...