Abstract: The nip pressure of a rotating roll is measured and displayed through the utilization of techniques which include the transmission and reception of electromagnetic radiation. A pressure transducer is mounted on the inner surface of a roll shell and connected through a bore of a roll shaft to a light transmitting circuit. The light transmitting circuit is mounted in a housing on the end of the shaft and includes a voltage/frequency converter connected to the pressure transducer for converting pressure indicative voltages to pulses. These pulses activate a lamp driver for energizing a lamp which is mounted for radiation along the axis of rotation. An electromagnetic radiation receiver, in the form of a phototransistor, converts the received radiation into an electrical signal which is displayed as a digital representation of nip pressure and/or as a voltage (pressure) profile on an oscilloscope.