This circuit is from an old American documentation and its use in motorcycles with 12 V is suggested to power 6V radios. The transistor can be the BD136 and BC548.
This different audio amplifier was found in a 90's Electronic Design. The circuit uses components...
This “test your nerves” game was found in old documentation. The SCR can be of any sensitive type,...
This circuit can handle 25 A unde a 32 V voltage using a hight power old transistor. This...