SCR Steady Hand (CB22098E)

This “test your nerves” game was found in old documentation. The SCR can be of any sensitive type, for example series 106.

Crystal oscillator (CB9637E)
Found in a 1980s American documentation, this circuit has a current consumption of only 1 mA. The...
Audio Millivoltmeter (CB12216E)
This audio millivoltmeter was found in a 1992 publication. It can still be assembled, as the...
Simple continuity tester (CB7955E)
This very simple continuity tester uses a small 1.5 V lamp (type used in flashlights). Can be...