Leak Detector (CB22456E)

We found this circuit in a Popular Electronics from 1992. The transistor is general purpose, assuming equivalent.

2 m range converter (CB20263E)
This converter for the 150 MHz band was found in an American documentation. Transistors are...
Microwave Field Strength Meter (CB5187E)
The sensor diode used in this circuit is the common type of germanium. Experiments may be made...
TTL Optical Receiver For Data Link (CB918E)
The SN72741 integrated circuit is nothing more than the version of Texas Instruments of the known...