Found in a Popular Electronics from the 90s, this circuit activates a recorder for automatic recording of telephone calls. The circuit was used with old cassette recorders of the time.
Frequencies from 1 to 10 MHz can be obtained with a small adjustment of the variable in a narrow...
This indicator, shown in the figure and suggested by National Semiconductor, causes an LED to...
This circuit is from 1999 documentation and the indicated power is PMPO for a load of 4 ohms. Two...