This circuit was found in a Popular Electronics from the 90's. It consists of the solid-state variation of the well-known grid-dip meter. MOSFET is a component not very easy to obtain these days.
This amplifier with complementary symmetry output and good sound quality was found in...
This IR light sensor circuit was found in the July 1992 issue of Radio Electronics magazine. It is...
The resistors R1 and R2 consist of 8 220 ohms x 2 W resistors connected in parallel. The...