P25 and DSTAR are naturals for cutting bandwidth. DSTAR is -26db @ +/-3 Khz, there abouts (going from memory) and the mask is similar to P25. Some of the new commercial designs will be either 6.25 or 2 talk paths in 12.5 (sharing a system/frequency - isn't that a novel idea?).
--- In [email protected], Mark Thompson <wb9qzb_gro...@...> wrote: > > > > www.arrl.org/announce/board-0907/ > > Minutes of the 2009 Second Meeting > ARRL Board of Directors > Teleconference â" July 17-18, 2009 > > > 29. On motion of Mr. Sarratt, seconded by Mr. Frenaye, the following > resolution was ADOPTED: > WHEREAS, there is current substantial amateur radio movement, activity, and > innovation in the digital narrowband area; and > >WHEREAS, the FCC has mandated that by 2013 commercial radio move to > >narrowband channels and Amateur Radio manufacturers normally follow > >commercial practices; and > >WHEREAS, the VHF/UHF Amateur Radio band plan currently uses 15 and 20 kHz FM > >channels; and > >WHEREAS, with the increasing use of narrowband across the country amateurs > >are placing and using narrowband equipment outside the repeater subband > >because there is no real place to fit the narrowband pairs; and > >WHEREAS, for ARRL to remain a respected leader in technology, we must be > >actively involved in innovative solutions to problems by bringing about a > >productive discussion on a technical paradigm shift; now > >THEREFORE, the President shall appoint a study committee for the purpose of > >research and to consider developing a plan to move the US amateur community > >to narrowband channel spacing. >
