This 6-transistor Japanese radio from the 1960s used germanium transistors and had an output power of 180 mW. The circuit is of the superheterodyne type with push-pull class B output.
This circuit appears elsewhere on this site. Although the 8038 is not an easily obtainable...
The Texas Instruments TPS80 LDO (Low Dropout) series (www.ti.com) can provide fixed or adjustable output...
Found in Radio Electronics, this simple indicator circuit uses general-purpose transistors common today....