Those go to a circuit board he designed which modulates the carrier with the audio signal using a single transistor and then sends the result out the ultrasonic transmitter. He took care to ...

[Chis] wanted an FM transmitter bug ... electret microphone and hits a transistor for amplification, the signal is then passed to the oscillator section of the circuit which features an LC ...

As with many inventions, two people had the idea for an integrated circuit at almost the same time. Transistors had become commonplace in everything from radios to phones to computers, and now ...