Found in a 90’s 73 magazine for radio amateurs, this circuit provides a few milliamps of output with -15 V from a 3 V input, when the consumption will be 10 mA.
This regulator type series for charging batteries from solar panels was found in a technical...
This circuit is from an English publication from 1965. The transistors used are rare, however, they...
This good quality stereo amplifier was found in a Japanese publication from the 1960s. The circuit...