This circuit was found in a Popular Electronics from the 90's. The transistors are general-purpose types and the loaded load depends on the voltage and must have a maximum current of 100 mA.
This circuit is from an English magazine of 1977. The circuit is still current, just using BC547...
This is yet another simple LED driving game circuit that appears in several other versions on this site....
The circuit, shown in the figure, is suggested by Texas Instruments, making use of one. Frequency is...