Institute Newton C. Braga

Circuit Bench

Ultra Simple Alarm (CB16385E)
We have in the figure an ultra-simple alarm found in a 1981 publication. As the author indicates, it is...
Battery Voltage Monitor (CB6066E)
This circuit is from an American 80's documentation. The circuit indicates when the voltage of a 9 V...
Variable High Pass Filter (CB25599E)
This variable high pass filter covers the range from 23 Hz to 700 Hz with the components used. The...