This unijunction transistor circuit is a frequency divider synchronized to 100 kHz. The circuit was found in a Radio Electronics from July 1968. The adjustment of R4 is important.
This simple radio was found in a Popular Electronics from the 90s. L1 and L2 have 100 turns on a...
This circuit was found in Radio Electronics magazine from the 90's. The circuit is for small NiCad...
This automotive circuit was obtained from an 80's schematic from the integrated circuit factory...