We found this circuit in documentation from the 1980s. The transformer is of the low voltage type with a 1: 3 turn ratio and the transistors can be of general-purpose types.
We found this configuration in a documentation for radio amateurs from 1974. The circuit can be...
Texas Instruments' low power operational amplifiers OPAx196 can be found on Mouser Electronics....
This low power amplifier circuit for speaker or phone is from the Philips Databook of 1990. The...