Noise and Interference Test Set 10MHz-200MHz The Agilent (now Keysight) 3708A Noise and Interference Test Set provides an accurate method of assessing performance of microwave radio and satellite systems by providing carrier-to-noise (C/N) and carrier-to-interference (C/I) to make C/N and C/I versus Bit-Error Ratio (BER) measurements. Bandwidth is 10 to 200 MHz. The unit can also be used to assess performance of digital TV forward error correction (FEC) by checking the tolerance of quasi-error-free systems to injected noise and interference.