The MR139H from Spectrum Control is a RF Mixer with RF Frequency 4000 to 18000 MHz, LO Frequency 4000 to 18000 MHz, IF Frequency 10 to 3000 MHz, Conversion Loss 6 dB, LO Drive - Power 18 dBm. Tags: Surface Mount, Double Balanced Mixer. More details for MR139H can be seen below.