Institute Newton C. Braga

Circuit Bench

Crystal test (CB9622E)
This circuit is one of many that the reader can find in this section for testing crystals. The...
Undervoltage and overvoltage indicator (CB5073E)
This circuit that uses only transistors indicates when the voltage in the circuit has the voltage...
Visual Test Nerve (CB16396E)
This circuit was found in a 1981 publication and consists of an interesting handicraft game. The...