Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The circuit uses components that are still common today.
This modulated light transmitter was found in a 90s Popular Electronics. In place of the lamp with...
On this website we show how to calculate the components of this circuit for other frequencies. The basic...
This circuit using only transistors was found in documentation from 1977. The frequency is 4250...