Found in a 1990 Hobbyst Handbook this circuit has an output power of a few tens of watts and serves as reinforced for the car's sound. The speaker can be 2 or 4 ohm.
In the figure we have a Texas Instruments circuit for TTL interfacing using discrete transistors. The two...
This circuit was found in Radio Electronics magazine from June 1963. The range is small and the...
The project presented in a 2009 documentation is intended for radio amateurs operating in the...