Non-contact RRR measurement technique for SRF cavities was designed, developed and tested using PCB based sensing elements and cold electronics based signal conditioning circuits capable of operating down to 4.2 K. An eddy current based sensing technique was developed and Niobium samples of known RRR values were used to determine the accuracy of the method. The passive components for cold electronics based signal conditioning circuit were selected based on the detailed behavioural study at 4.2 K. Reliability of the signal conditioning circuit was studied in detail by subjecting it to thermal cycling. Thickness measurement of multiple samples coated with different thickness of niobium was conducted using the multilayer planar inductor based sensors.