The NX153HZ from Narda-ATM is a Noise Source with Frequency 1 to 18 GHz, Excess Noise Ratio (ENR) 15.5 dB, Flatness ±1.2 dB, Temperature Coefficient 0.01 dB/Degree C, Voltage Coefficient 0.1 dB/%V. Tags: Module with Connectors. More details for NX153HZ can be seen below.