MMCX to SMA Cable Assemblies Amphenol RF MMCX to SMA Cable Assemblies feature an SMA jack to MMCX plug using an RG-316 cable. The cable assemblies offer 50Ω impedance, DC to 6GHz frequency, 300VRMS hipot, and up to 5% tolerance. Amphenol RF MMCX to SMA Cable Assemblies come in lengths of 0.152m to 3m (6' to 118.11') with a straight, right-angle, or bulkhead connector body style.