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.
Found on Popular Electronics from the 1990s, this oscillator uses a general purpose transistor. The...
This circuit was obtained from National Semiconductor documentation from the 1990s. The circuit has a...
We found this circuit in a 2005 Linear Technology manual. Observe the component values and...