Talkgroup Mode change?

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troymail

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Noticed recently that the talkgroup "mode" column has changed - "trailing E and e", etc....

I've always been somewhat puzzled by this column - particularly with regard to "D" vs. "T"...

I noticed today that the Maryland FiRST system - which is by default fully a TDMA system (unless a Phase 1 radio appears on a talkgroup) - has been modified and those talkgroups changed to add the trailing encryption indicator are "DE" vs. "TE"...

Oversight? Intended?

Just curious.
 

RBMTS

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D or E (upper case) means that the digital or encryption is full time on.

d or e (lower case) means that the digital or encryption is partial / part time.

If you hover your pointer over the "Mode" heading it will give you an explanation.

Good point about the TE - I just saw that on your thread.
 
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troymail

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D or E (upper case) means that the digital or encryption is full time on.

d or e (lower case) means that the digital or encryption is partial / part time.

If you hover your pointer over the "Mode" heading it will give you an explanation.

Understood - maybe I wasn't clear ... why are the full or partial encrypted talkgroups being changed from "T" or "E" to "DE" (or "De")?
 

RBMTS

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I just caught that and edited my post. Good point.
 

emtLarmy15

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Your statement about first being phase 2 unless a phase 1 radio appears isn't true across the board. Two weeks ago we were testing new profiles. My radio would affiliate on md call and all tacs. On the other hand it wouldn't affiliate on any MSP groups. Figured out tdma capable wasn't checked in the build of the system... so, whether intended or not, MSP talkgroups are phase 2 only.

So in the end how can we even tell if a tdma talk group is even fdma capable unless it allows a phase 1 to affiliate? I only ask because I wonder where the database got its info to change the Ds to Ts
 

troymail

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Your statement about first being phase 2 unless a phase 1 radio appears isn't true across the board. Two weeks ago we were testing new profiles. My radio would affiliate on md call and all tacs. On the other hand it wouldn't affiliate on any MSP groups. Figured out tdma capable wasn't checked in the build of the system... so, whether intended or not, MSP talkgroups are phase 2 only.

Right - that's been an issue in my head for a long time. The column heading/description says that "T" means "capable" which is a bit wishy-washy.... FiRST is full-time TDMA - that is, I do not believe ANY are intended to be full-time Phase 1 (FDMA) because that wastes system resources.

Point being is that labeling talkgroups as "TDMA capable" is a bit backwards -- it really should be (sort of) the other way around ("TDMA but capable of being FDMA", etc.).

Of course there is the long standing issue that in some cases the submitter just doesn't know and the admins default for a P25 system (I believe) is to simply label things FDMA ("D"). Example - Adams County Public Safety -- to my knowledge - is fully TDMA as well but all talkgroups are labeled "D"...

It's all just a bit confusing....

And to add to the user's (future) confusion - as I understand it - today, if a Phase 1 radio affiliates on a TDMA talkgroup, the talkgroup reverts to Phase 1 on all sites that talkgroup is active on. New features will change this such that only the site(s) with the non-Phase 2 radio(s) will revert to Phase 1 while others carrying the talkgroup will remain in Phase 2...

Sorry 'bout that last part -- but all of these things go into confusion for some (newer, etc.) users...
 
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RBMTS

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Also I mis-quoted above. There is no lower case "d" or "t". for digital mode. That attribute stays the same as it was. Only the encryption attribute was added to allow full time or part time encryption.
 

Spitfire8520

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Noticed recently that the talkgroup "mode" column has changed - "trailing E and e", etc....

I've always been somewhat puzzled by this column - particularly with regard to "D" vs. "T"...

I noticed today that the Maryland FiRST system - which is by default fully a TDMA system (unless a Phase 1 radio appears on a talkgroup) - has been modified and those talkgroups changed to add the trailing encryption indicator are "DE" vs. "TE"...

Oversight? Intended?

Just curious.

It appears that everything that formerly had "E" mode was mass converted over to "DE" to support the rework in how encryption is displayed. There was no way to determine if the old "E" meant "DE" or "TE" for specific systems since it was a database wide change. It would appear that all the database admins/users need to check their systems and ensure that the proper modes are being used.

As for whether "D" vs "T" is more appropriate, I would think that any talkgroup that operates in TDMA mode for any period of time should be given the "T" mode. The database should be providing an idea of what scanner is needed to listen to a talkgroup 100% of the time. A TDMA capable scanner can handle either mode automatically, but a older digital scanner obviously cannot handle the newer mode.

As for incorrect modes outside of the changes to the "E" mode, that appears to be a database admin/user oversight and should be corrected.
 

crazyboy

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Why is it D instead of F for FDMA? Theres plenty different modes of digital.
 

emtLarmy15

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I would suspect for just that reason (simplicity). There's many types of analog trunking as well (edacs, smartnet, etc) but you can only have certain digital voice with certain systems (pro voice with edacs, fdma with smartnet)

With tdma there's only one type.
 

Project25_MASTR

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I would suspect for just that reason (simplicity). There's many types of analog trunking as well (edacs, smartnet, etc) but you can only have certain digital voice with certain systems (pro voice with edacs, fdma with smartnet)

With tdma there's only one type.



I'm leery of that as a manufacturer has it in their plans to have infrastructure capable of doing P25 (either phase) or DMR as a software defined option. The idea is the repeater can be dynamic as long as it's not a control channel. I.E dedicated control channels, dynamic voice/data channels capable of whatever kind of resource is called for.


Sent from my iPhone using Tapatalk
 

ThePhotoGuy

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Your statement about first being phase 2 unless a phase 1 radio appears isn't true across the board. Two weeks ago we were testing new profiles. My radio would affiliate on md call and all tacs. On the other hand it wouldn't affiliate on any MSP groups. Figured out tdma capable wasn't checked in the build of the system... so, whether intended or not, MSP talkgroups are phase 2 only.

Interesting... I know other talkgroups do revert to FDMA when Phase I radios affiliate; MDTA (BCPD affiliates), Queen Anne/Caroline (Delaware Users affiliate), MEMA Central I (Baltimore Env Police Users). I wonder if it is an error for MSP or it was intended? I wonder if is across the board or just the lower shore MSP talkgroups?
 

troymail

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Why is it D instead of F for FDMA? Theres plenty different modes of digital.

My guess is back in the day, Digital was the shiny new thing everyone saw replacing Analog so it seemed obvious.... and now there's all these different types of digital.

If you have things dependent upon the A or D (or T), it's hard to go back and change them. If anything, you might see a new column added in the future... but who knows.
 

troymail

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Your statement about first being phase 2 unless a phase 1 radio appears isn't true across the board. Two weeks ago we were testing new profiles. My radio would affiliate on md call and all tacs. On the other hand it wouldn't affiliate on any MSP groups. Figured out tdma capable wasn't checked in the build of the system... so, whether intended or not, MSP talkgroups are phase 2 only.

So in the end how can we even tell if a tdma talk group is even fdma capable unless it allows a phase 1 to affiliate? I only ask because I wonder where the database got its info to change the Ds to Ts

This is one of the problems with crowd sourced information from us folks in the hobby... we just don't know. Just like we don't know which talkgroups are allowed on which sites and which radios are allowed on which talkgroups. Examples:

FiRST - statewide talkgroups (MDTACs, etc.) vs. county talkgroups (Kent, Talbot, QA, Caroline, etc.) - every FiRST radio (and probably many none FiRST radios) probably have the MDTACs but the county talkgroups are likely much more limited as far as sites.

Prince George - I believe there were originally some talkgroups that are/were ALWAYS Phase 1 (FDMA) - see: TGID 293 / PGPD A FDMA

Of course, for the most part, none of this is written in stone either and can change without notice if the admins/system owners feel the need to do so.... and, with some (few) exceptions, they aren't going to tell us. It's all part of the puzzle...
 
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