This circuit is from a Hands-On Electronics from the 90s. The integrated amplifiers used are well known. The range is a few tens of meters depending on the resistance of the cables.
We find this battery charger in a 90's Hands-On Electronics. The charging current is 2 A and when...
This circuit has 4 operating modes and was found in the 1995 Encyclopedia of Electronic Circuits...
The circuit shown in the figure converts a sinusoidal signal of convenient amplitude into a CMOS...