NPN and PNP transistor tester (CB22146E)

This simple transistor tester was found in old English documentation. Suitable for general purpose transistors.

0.25 Hz Servo Shaker (CB19801E)
What this circuit does is to agitate a servo at a frequency of 0.25 Hz, which can be used in...
Ring Modulator (CB4227E)
This circuit is suitable for SSB modulation and was obtained from an amateur radio documentation from...
CW tone generator (CB21673E)
This telegraphy circuit generates an audio tone from a pure RF carrier. We found it in a...