This high quality circuit with complementary symmetry was found in an Electronics World of 1966. It can be made with modern transistors like the BD or TIP series.
This circuit from a June 1957 Radio Electgronics is for oscilloscopes of the time with a maximum...
This circuit is from an English magazine Radio and Electronics Constructor of November 1978. The...
This circuit was obtained from a Linear Technology manual from the 90's. The integrated circuits are...