This circuit was found in an 80's EDN. The circuit uses a current common CMOS, the 4093 powering an LED. Trigger adjustment is done in a trimpot.
In the figure we have a simple signal tracer circuit to be coupled to the volume control of an AM...
This circuit was found in documentation from the 90s, using components from that time. The...
This circuit, obtained from old documentation, allows the recovery of sulfated batteries. The...