Key Specifications. Minimum Frequency 18 GHz Maximum Frequency 26.5 GHz Typical Attenuation Value, Min 0 dB Typical Attenuation Value, Max 30 dB Insertion Loss 0.3 dB Maximum Input Power 0.3 Watt VSWR 1.15:1. WR-42 Waveguide Continuously Variable Attenuator, 0 to 30 dB, from 18 GHz to 26.5 GHz, UG-595/U Square Cover Flange, Dial., Pasternack’s Continuously Variable Waveguide Attenuators are offered for the frequency range of 18 to 110 GHz in different waveguide bands. The attenuation value of the Continuously Variable attenuators are from 0 to 30 dB with full waveguide operational bandwidth. The Continuously Variable attenuators are equipped with a micrometer, which enables rapid re-setting. With calibrated charts, attenuators can be used as direct reading attenuator for bench top test set use. The level setting attenuators are typically used in the test setups and prototype assemblies where certain attenuation is required.