Optical radiators and power meters are used to test the optical receivers in industrial bulk production. By the use of optical radiator, the variable data transmission is done as the form optical source. The radiator varies the intensity of the optical source by varying the diameter of bushes by mechanical methods. At the receiver, the power meter is used to calculate the amount of power received. Optical receivers are used to acquire the data (in the form of signals) for long-range medium. Testing of the receivers is by combining the power meter and radiator. Optical receivers are tested with different tests like zero drift, sensitivity, and transfer coefficient. Sensitivity tests are of two types, depending on the supply voltage of ±11V and ±15.5V. Zero drift is calculated to check whether any pin other than the output pin is acquiring any of the signals. Sensitivity defines the receiver response with the source. © Research India Publications.