This 9-pixel circuit has been implemented with 9 LDRs and can be coupled to a processing system for an elementary artificial eye. The circuit is from Radio Electronics, November 1986.
The frequency of this Pierce oscillator, found in 1969 documentation, depends on the crystal. The...
We found this Nicad cell charging circuit in an English publication from the 1970s. The circuit can...
In the figure we have a constant current source for Shape Memory Alloy in wires or Alloy with...