I am studying a schematics where the non inverting input of an op amp controls what looks to be a voltage controlled resistor (VR202). Without this component, I think the op amp would work as an integrator or an amplifier with a certain AC bandwidth, but I am not sure what this additional component does. To me it looks like it changes the gain of the amplifier so that the output of the op-amp is regulated faster , am I remotely correct ?
Additional information: On the manual related to the device I am studying (an analog isolator with variable gain SIM 984 from SRS), one can read :"The overall AC gain is trimmed using VR202 at the factory, and should not require user adjustment." What is trimmed here if the component is voltage controlled ?
The full schematics can be found on (https://xdevs.com/doc/Stanford_Research_Systems/SIM900/sim984_sch.pdf)