The circuit is from a June 1995 Electronics Now. The relay is power-dependent and both R1 and R2 should have close resistances in operation.
The operational amplifier used in this configuration is uncommon today, but more modern types can...
This is a circuit that appears several times in this section and in articles. It is a preamplifier for...
We found this circuit in the August 1994 issue of Electronics Now. The 4046 is unusual today. The...