The MDL520 from R & K Company Limited is a RF Mixer with LO Frequency 0.1 to 250 MHz, IF Frequency DC to 500 MHz, Conversion Loss 5.5 to 8.5 dB, LO Drive - Power 7 dBm, P1dB 1 dBm. Tags: Drop-In, Double Balanced Mixer. More details for MDL520 can be seen below.