The ZN416E integrated circuit is uncommon today. It consists of a complete radio, like the one found in a 90s Popular Electronics. The power is from a single battery.
Using a BA1404 integrated circuit this small FM stereo transmitter was found in a Radio...
The operational amplifier is not very common today, but in its place an equivalent, even of...
This circuit was found in the February 1993 Radio Electronics magazine. The frequency depends on...