Hi,
The RF ports of both HMC939 and HMC941 have same line potential of ~0Vdc so the connection between these parts does not require DC blocking capacitor.
These parts are scheduled to be discontinued in late 2016. At least 6 months before the discontinuation, the official PCNs are published to notify Last Time Buy date and recommended replacement parts. Replacement part numbers will be HMC939A and HMC941A. The development could be started with HMC939 and HMC941, then migrated to HMC939A and HMC941A which will support same operating conditions/electrical performances, targeted as drop in replacements. Or we can offer HMC1018LP4E and HMC1019LP4E instead, if the application is convenient for using plastic QFN packaged and serial control parts.
Regards