Leak Detector (CB22456E)

We found this circuit in a Popular Electronics from 1992. The transistor is general purpose, assuming equivalent.

20 W BTL Automotive Amplifier TDA2005S (CB15241E)
This circuit has a gain of 34 dB and a good power to be used as an audio booster in cars. The...
3 W Amplifier (CB6201E)
This circuit was obtained from Dutch documentation from 1967. It uses transistors of the time...
Headlamp timer 2 (CB6050E)
Found in an Electronic Design this circuit controls a headlamp by triggering a time determined by the...