HEWLETT PACKARD HP 349A UHF Noise Source
The HP 349A UHF Noise Source consists of argon gas discharge tubes in Type N coaxial configuation for automatic noice figure readings, 0,4 to 4 GHz frequency range. Excess Noise Ratio is 15.6 dB, ±0.6 dB. Maximum SWR 50Ω is 2.0 (ON).