Database Question

[etihparg]

On the RR database, under mode there is "Digital" and "TDMA Capable". Both systems are Apco Project 25 Phase II. What's the difference?

 

[ka3jjz]

Which entry specifically? Mike

 

[GTR8000]

It refers to the talkgroup modes.

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

 

[marksmith]

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]

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]

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.

Database Administrator Handbook Live Version - The RadioReference Wiki

wiki.radioreference.com

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]

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.

 

[rogress]

I have a question about the below. Where do we find the "cross reference" that tells us what the talkgroup modes equate to. I have learned over time what the uppercase T means, but where is that stuff actually published. I have never been able to find it.

Thanks.

It refers to the talkgroup modes.

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

 

[fxdscon]

I have a question about the below. Where do we find the "cross reference" that tells us what the talkgroup modes equate to. I have learned over time what the uppercase T means, but where is that stuff actually published. I have never been able to find it.

Thanks.

Tap (or hover your mouse pointer) on the “MODE” header at the top of the mode column in the database. A pop up window will show the meanings.
.

 

[rogress]

Tap (or hover your mouse pointer) on the “MODE” header at the top of the mode column in the database. A pop up window will show the meanings.
.

Thanks! Never did see that. I'm good to go.