[Scan-DC] Loudoun County nonsense

[Jeff Krauss]

TDMA has been around for a long time.
Satellite systems have used TDMA since the 1980s.
The GSM Cellphone standard uses a flavor of TDMA.
So it should not be a major technical problem.


At 10:25 PM 12/14/2009, Eric C. Carlson wrote:
>Unfortunately, I don't know the answer to that.
>
>-Eric
>
>On Mon, Dec 14, 2009 at 9:09 PM, Jeff Krauss <jeff at krauss.ws> wrote:
> > Thanks for the intelligible explanation.
> > Do we expect that scanners capable of P25 Phase 1 can have 
> firmware upgrades
> > to support Phase 2?
> >
> > At 09:59 PM 12/14/2009, Eric C. Carlson wrote:
> >>
> >> Some P25 systems are starting to use TDMA digital voice, which no
> >> scanner can currently decode.  So your P25 digital scanner would be
> >> like having an old analog scanner: you won't be able to hear anything.
> >>  Your existing digital scanners support what is known as P25 "Phase 1"
> >> digital voice.  P25 "Phase 2" is starting to appear (or at least a
> >> not-yet-officially-finalized version of it).  You can read more about
> >> this at radioreference.com.
> >>
> >> http://wiki.radioreference.com/index.php/Project_25#Project_25_Phase_II
> >>
> >> Systems using Phase 2 audio may also use Phase 1 audio (it's still
> >> there for backwards compatibility).  Think of it like Motorola systems
> >> that have both analog and P25 talkgroups.  Except in this case a given
> >> talkgroup that is normally Phase 2 could revert to Phase 1 audio if a
> >> Phase 1 radio joined the talkgroup.
> >>
> >> -Eric
> >>
> >> On Mon, Dec 14, 2009 at 8:40 PM, Jeff Krauss <jeff at krauss.ws> wrote:
> >> > Can someone translate the nonsense messages about Loudoun County into
> >> > plain English?
> >> > My scanner can receive P25 just fine.
> >> > So what if they convert from Motorola to P25?
> >
> >