This circuit of a Popular Electronics from the 90s makes use of components of the time. The circuit has sampling and retention capabilities and a conversion rate of 1V / kHz.
The circuit shown is based on National Semiconductor buffers and was found in the 1994 Linear...
This metal detector was found in a French magazine Radio Plans from 1977. The phone can be a...
This metering bridge circuit uses one power supply only. The operational ones depend on the...