Frequency to voltage converter (CB6993E)

Found in Popular Electronics from the 90s, this circuit can be used in tachometers. The integrated circuit is not a common component today.

| Clique na imagem para ampliar |

Reflex receiver (CB20557E)
This 1-transistor reflex receiver was found in a 1963 publication. The coil is for the mid wave...
Device On indicator (CB7014E)
Found in a European magazine from the 90s, this circuit emits beeps that are several seconds apart to...
Instrumentation DA Interface (CB18758E)
This interface or shield circuit for instrumentation was obtained in a publication from the 90's....