Low power double-balanced mixers work from VLF through 4-GHz - EE Times
AD831 High Frequency Transducer RF Mixer Module 500MHz Bandwidth Mixing Down Mixing Dual Balanced Mixer Single Chip Radio Frequency Converter -10dBm: Amazon.com: Industrial & Scientific
IC - DOUBLE BALANCED MIXER AND OSCILLATOR VCC = 6V TYPICAL 8-LEAD DIP: Transistors: Amazon.com: Industrial & Scientific
LT5575's mixers are double balanced mixers? - Q&A - RF and Microwave - EngineerZone