This circuit transmits in the FM band. It is a good range FM transmitter found in a 90's Silicon Chip documentation. The integrated circuit used can be difficult to obtain.
This circuit is from a 1995 publication. The components are all common and the number of LEDs may...
This circuit, found in a 1995 documentation, is intended for switching composite RGB video signals...
This circuit is from Motorola's Linear Interface ICs of 1993. The integrated circuit is not common...