This circuit was found in a 1977 documentation. With it we have the direct indication, through LEDs of an ASCII signal. The circuit must be powered by a voltage of 5 V.
In the figure we have a signal detector using a tunnel diode. The circuit is from a Radio...
We found this 2-transistor circuit in Radio Electronics magazine from July 1961. The circuit is...
This circuit or practical idea comes from a time when cheap solar cells were not available (1992). What is...