Database Question

etihparg

Member
Premium Subscriber
Joined
Dec 25, 2002
Messages
78
Location
Gilbert, Arizona
On the RR database, under mode there is "Digital" and "TDMA Capable". Both systems are Apco Project 25 Phase II. What's the difference?
 

GTR8000

NYS Database Guy
Database Admin
Joined
Oct 4, 2007
Messages
8,132
Location
BEE00
It refers to the talkgroup modes.

D = FDMA (Phase I)
T = TDMA (Phase II)
 

marksmith

Member
Joined
Jun 20, 2007
Messages
4,154
Location
Anne Arundel County, MD
Generally, phase II systems are capable to fall back to phase I. It does not work the other way.

Some early TDMA phase II systems initially start as FDMA phase I systems because they have not migrated all of their radios to TDMA. These are often shown as "TDMA capable" but they are using FDMA until all radios are phase II. These systems can accommodate both until all radios are migrated. Then generally all comms will be TDMA unless they are affiliating with Phase I radios for mutual aid or other cross systems traffic.
 

Mr_Boh

Member
Joined
Oct 10, 2016
Messages
307
Location
The Land of Pleasant Living
Slightly on the same topic - I have been told different things by different administrators and wanted to know what the "most correct" answer is.

Some systems report via tools like Unitrunker that they are TDMA capable (band plan shows channel IDs with 2 slots), however the talkgroups are all FDMA (and it's known that pretty much all users operate Phase I equipment only, such as XTS5000). I was told by the administrator it would not be marked as "Phase II" until a TDMA talkgroup popped up. Yet some systems, such as Fairfax County, VA show "Phase II" with all FDMA talkgroups.

Should we be reporting systems broadcasting TDMA capabilities as phase II?
 

GTR8000

NYS Database Guy
Database Admin
Joined
Oct 4, 2007
Messages
8,132
Location
BEE00
Slightly on the same topic - I have been told different things by different administrators and wanted to know what the "most correct" answer is.

Some systems report via tools like Unitrunker that they are TDMA capable (band plan shows channel IDs with 2 slots), however the talkgroups are all FDMA (and it's known that pretty much all users operate Phase I equipment only, such as XTS5000). I was told by the administrator it would not be marked as "Phase II" until a TDMA talkgroup popped up. Yet some systems, such as Fairfax County, VA show "Phase II" with all FDMA talkgroups.

Should we be reporting systems broadcasting TDMA capabilities as phase II?
The definitive answer can be found in the online Database Administrator Handbook in the Wiki.


Trunked Data
General

Trunked systems shall always be entered with the “highest level” mode of operation for which it is confirmed to be capable. For example, enter a Project 25 system as “Phase 2” type if it is confirmed to be Phase 2 capable even if it has no TDMA talkgroups confirmed in use yet.
 

wa8pyr

Technischer Guru
Lead Database Admin
Joined
Sep 22, 2002
Messages
4,690
Location
Ohio
The only exception to the rule in the handbook is in cases where a system is confirmed to be Phase I only and not physically capable of Phase II operation. This is pretty rare.
 
Top