This longwave signal booster circuit was found in the 1995 Encyclopedia of Electronic Circuits Volume 5. Note the dimensions of the board. The transistor is a general-purpose transistor.
This circuit decodes a 1800 Hz tone used in communications. The circuit is from an American...
These two circuits were found in Radio Electronics magazine from February 1960. The transistor is a power...
With the development and availability of small LCD screens for automotive use, especially in...