[MilCom] USN Digital LMR's Other Than A/C Carriers?

[Ken]

Last evening "The Military Channel"  'Military Show Case' had a segment 
called "Operation Sea Dragon"...
http://military.discovery.com/tvlistings/series.jsp?series=116341&gid=13679&channel=MIL
 One of the boarding teams inspecting a civilian tanker was utilizing radios 
that when they pressed the button their would be a beat & than the 
individual would transmit.  Isn't this an indication of digital radio 
system?  Also part of the inspection team was below deck but appeared to be 
able to communicate very well with the boarding team commander who was up on 
the bridge.  I'm wondering if a portable repeater was on the small boat they 
used to respond to the ship or perhaps the helo support had a repeater?

The show repeats one more time this month (0300 hrs local edt).  Perhaps 
taping the show (which I'll have to figure out how to do with digital cable) 
may add some insight as to what is the mfg/model the radio equipment being 
used.

Ken