This circuit also appears elsewhere on this site, obtained from other sources. This is an 80's American schematic book. Instead the lamp can be used white high-brightness LEDs.
The purpose of this circuit is to eliminate RF picked up by a turntable. The circuit is from a...
This old circuit, found in a 1975 documentation, was designed to limit, and filter signals from...
This circuit can be implemented with common components operating with low-intensity signals. The...