This benchtop power supply with various output voltages from 1.5 to 12 V was found in Radio Electronics magazine from August 1960. The circuit uses power transistors of the time.
This sequential light effect was obtained in a 1992 documentation, but it can be easily assembled...
This simple Hartley circuit can generate two tones depending on the adjustment of the trimpots. The...
This 2.5 A power supply was found in a 90's QST magazine. The power transistor must be mounted on a...