This anti-theft circuit was found in a 1985 documentation. It uses common components that can still be found easily. The relay is 12 V and the circuit has timings of 3 minutes and 20 seconds.
Based on common components, this circuit was found in an English publication. The circuit is...
This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply...
In relation to the previous circuit (CB18493E) this spy has an extra transistor, which can be a...