We found this circuit in Radio Electronics from the 90s. The components are current. The sensor is a common general-purpose transistor. The connection to the sensor is made by twisted pair.
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...