On May 9, 2008, at 5:47 PM, Nate Duehr wrote: > Dan Blasberg wrote: > >> No, P25 decoder is built into the radio itself, much like the ICOM >> radios. > > Not 100% true. Raytheon JDS will hook an external P25 encoder/decoder > to your existing repeater. You ship them the repeater and $10K, and > they'll ship it back when they're done.
Forgot about the Raytheon piece of kit, thanks Nate. > > >> And no one has come out with a "dongle" for P25 probably due >> to the expense of the codec from DVSI for IMBE. That may change for >> phase 2 P25 which will be using an AMBE codec from DVSI. The >> question >> is, is it the same AMBE codec used for D-Star and if so, can someone >> write the firmware into a dongle to add both P25 and D-Star to the >> same radio. If that were to happen that would be pretty kick. > > AMBE is AMBE. The framing/encapsulation of that AMBE in a P25 or D- > Star > overall bitstream is completely different, but if you can figure out > how > to copy the frames, you can extract the AMBE bits and shove them > through > DVSI's CODEC to get audio, and vice-versa. Not according to DVSI, they have several flavors of AMBE (AMBE-300, AMBE-2000, AMBE-2020, AMBE-20x0-HDK, AMBE-1000) and not all of them are AMBE+2 compatible, so AMBE is not AMBE especially when talking AMBE and AMBE+2. If they use the same compression scheme and chipset then a dongle shouldn't be a problem, if they use different chipsets and schemes then I guess the question is how hard would it be to come with a Dongle for P25, since one already exists for D-Star? > > > DVSI sells a chipset that's roughly $25 each in small quantity to > handle > the AMBE CODEC part of the job. > > Nate WY0X > > ------------------------------------ > > > > Yahoo! Groups Links > > >
