Question:  I currently have the CS-702 base station and RS-603 headsets... I am looking to add a wireless system that can be combined with our current system. Will the HME-DX210 Wireless System connect with our system? How do we do that? Is there any special equipment needed?
On the HME-DX210 manual, I've noticed that it has a diagram with the PS702 and RS601 connecting to the HME-DX210 but not our system.
Answer:  The DX210 supports both Clear-Com and RTS cabled 2-wire intercom systems, and also has 4-wire and auxiliary audio connections. 
The DX210 supports two channels of 2-wire unbalanced intercom, it will support the CS-702 main station and RS-603 beltpacks via a TWC-701 interface.  The DX210 supports 2-wire nulling and input and output level adjustment.