JK 4037 Flip Flop with Reset (CB25121E)

We found this circuit in the April 1988 issue of Radio Electronics magazine. The circuit can be reset electronically.

DC Motor Control (CB12292E)
This circuit is from 1977 documentation, but can be assembled with BC548 for Q1, Q2 and Q4, BC558...
FET caracteristic curve plotter (CB20730E)
Found in American documentation from the 90s, this circuit uses components that are still common...
Piezoelectric Mike Preamplifier (CB786E)
This high impedance input amplifier is suitable for the use with piezoelectric sources such as...