This circuit with power MOSFETs was found in a 1980s Siliconix documentation. Equivalent MOSFETs can be used, as well as other transistors. Note the symmetric power supply.
This circuit was found in a QST from the 1990s. The circuit expands the scale of a 10V instrument to...
This 8 ohm output amplifier was found in a 1968 Motorola publication. The circuit uses transistors...
This general-purpose preamp configuration was found in the 1960 Mullard transistor reference...