Would like to know if a HDMI output from a 722 DVR can be split to HDMI and a coax output?
It would be better to explain what you're trying to accomplish. Not just the "split hdmi" but what is the end point? you want to hook up two TV's? and one of them is old, having no other connectors ?? etc..
Also understanding the nature of HDMI .. as time is moving on, companies are calling on enforcement of HDCP, and in the licensing spec for HDMI/HDCP (HDMI licensing *not* HDMI specs) any analog output is to be denied on HDCP protected content enforcement. The push is currently coming from HBO .. its only a matter of time before others start doing it too.
So ... what were you trying to accomplish (and confirm please, 722 or 722k receiver?)