This unusual circuit from a Popular Electronics of the 90s uses LED indicators, operating as a bridge. The components used are common. It is based on the tuning of the signal by a PLL.
This circuit was obtained in an old Argentine publication, using germanium transistors and...
This very low resistance meter was found in the February 1995 issue of Electronics Now magazine. The...
Using a CA3130 operational amplifier, this circuit was found in an English publication from 1977....