This noise limiter for low intensity signals was found in a 73 magazine for radio amateurs from the 90's. The circuit is for signals from 10 mV to 1 V amplitude.
This simple circuit uses a 200 µA galvanometer to measure voltages in three ranges. The circuit...
Today we can call this circuit a baby monitor. It is a microphone amplifier found in a publication by...
This circuit is from Motorola's Linear Interface ICs from 1993. The MC1723 is the equivalent of...