Found in a Motorola documentation from the 70s, this circuit makes use of transistors of the time. Modern equivalents can be used. The diode also supports an equivalent.
Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The...
This single-channel remote control transmitter operating in the FM range uses common components and...
Although it is a common configuration today, this circuit was taken from an old publication. The...