This circuit is from a publication from the 70s. The operational amplifier is from the period. Modern equivalents according to the motor current must be used.
We found this circuit with an operational transconductance amplifier in the Motorola Linear...
We found this circuit in the 1994 Linear Applications Handbook by National Semiconductor. The...
In the figure we have a differentiator with the LM3900 transconductance amplifier. The circuit is...