This is a typical point scale or moving bar circuit with the LM3915. We found it in old American documentation. The operational amplifier supports an equivalent modern type.
In this circuit we show how it is possible to control a high power load (which depends on the...
Texas Instruments' low power operational amplifiers OPAx196 can be found on Mouser Electronics....
This circuit by Ferranti, in a 1967 publication, is intended for reading perforated tapes. The...