SFS-04-NB is a WR-04 subharmonically pumped mixer. The mixer is designed with high performance GaAs Schottky diodes and accepts an LO frequency at half the RF frequency to cover the frequency range from 170 to 260 GHz. With a low LO frequency range of 85 to 130 GHz, this mixer is well suited for low-cost WR-04 system solutions due to local oscillator frequency requirement. The mixer provides 30 dB 2LO to RF isolation, and 30 dB LO to IF isolation typically. The subharmonically pumped mixers in other frequency bands are offered under various model numbers.