Audio Cable Tester (CB3827E)

This simple circuit tests both monophonic and other two-wire audio cables. The circuit is powered by two common batteries.

Proximity Alarm (CB16505E)
This proximity (capacitive) alarm triggers a relay that, in turn, triggers an audible warning...
SCR Rain or Leak Alarm (CB22097E)
This sensitive circuit was found in old documentation. The SCR can be any of the 106 series and...
Light Triggered Oscillator (CB14950E)
This traditional multivibrator configuration uses an LDR as a sensor. The circuit emits sound when...