We found this circuit in an 80's manual. The same configuration can be adapted to make use of modern operational amplifiers. The power supply is symmetrical.
It can be obtained from Mouser Electronics new TPS54A20 Texas Instruments consisting of step-down...
This physical line servo control uses components that are not currently common. The circuit is from...
This circuit was found in 1968 General Electric documentation. The circuit uses components from the era...