Transistor Tester (CB21956E)

This transistor tester was found in a publication by Gernsback from 1960. The circuit can be used with current transistors.

Linear Ramp Generator (CB18910E)
We found this circuit with unijunction transistor in an old publication from the 80's. The circuit...
Ultrasonic Siren (CB18490E)
This simple emitter can be used in animal conditioning, to scare animals and even in biology...
VHF Receiver (CB21204E)
Found in an older Radio Craft, this circuit covers the aerial band from 118 to 136 MHz. No...