Are all TGID's Five digits?

[johndh]

Looking at the manual for the uniden 246T,I noticed that the talk group I.D. are suppose to be five digits.When looking at Peel police talk groups,some have only two digits.(link below)
Do I just enter 16 for the t.g.i.d. example to listen to 11 division or am I missing something?The reason for the question is because after programming in the Peel talk group I.D.s,the signals seem off freq. or fade abit in and out.(I live in Peel).Almost sounds like a simplex frequency or the input frequency of a repeater for those who are familiar with that example.
Thanks in advance.
http://www.radioreference.com/modules.php?name=RR&sid=1573

 

[UPMan]

Motorola and P25 channels can be from 2 - 5 digits. Yes, for TGID 16, just enter "16".

The TGID does not have any direct correlation to the frequency the scanner tunes to. If you enter a TGID incorrectly, you just won't ever receive that channel (the scanner will never see it as active on the system).

Sounds like you have a reception issue...improve location or antenna and see if things change.

 

[plaws]

Motorola and P25 channels can be from 2 - 5 digits.

And believe me, UPMan would know.

For the record, assuming that the highest and lowest numbered groups are valid, there are 4096 possible groups on a Mot system. I've heard, though, that it may not even be that many and may be only 2048.

On a non-P25 system, Uniden takes the real TG ID (see the "hex" column in the database) and adds another 4 bits to it (the status bits) and converts the whole thing to decimal.

It *looks* like there can be 65536 talkgroups (64k), but in reality you have to divide that by 16 (which has the effect of removing those 4 status bits) and may even have to divide it by two again.

 

[wlmr]

And believe me, UPMan would know.

For the record, assuming that the highest and lowest numbered groups are valid, there are 4096 possible groups on a Mot system. I've heard, though, that it may not even be that many and may be only 2048.

On a non-P25 system, Uniden takes the real TG ID (see the "hex" column in the database) and adds another 4 bits to it (the status bits) and converts the whole thing to decimal.

It *looks* like there can be 65536 talkgroups (64k), but in reality you have to divide that by 16 (which has the effect of removing those 4 status bits) and may even have to divide it by two again.

Depends on the system. On true P25 systems (9600 baud control channel) the TG IDs use every one of the 64K numbers with 0 and 65535 reserved for system use. (1 straight through 65534) No dividing by 16 or 32. When UPMan is referring to the IDs being between 2 and 5 numbers in size, how is an id like 1 or 4 or 7 or 9 programmed into a scanner?

 

[slicerwizard]

For the record, assuming that the highest and lowest numbered groups are valid, there are 4096 possible groups on a Mot system. I've heard, though, that it may not even be that many and may be only 2048.

Going from memory here,

Talkgroups 1 through 4000 (plus 4095) are valid on 3600 bps (e.g. "Motorola") 800 MHz systems.

1 through 4095 should be valid on 3600 bps systems that use other bands (VHF/UHF/900)

Talkgroup 4095 is a sitewide (or systemwide) call (all radios hear it)

Of course, scanners multiply talkgroup numbers by 16. Sure would be nice if they'd stop doing that.

 

[wlmr]

Of course, scanners multiply talkgroup numbers by 16. Sure would be nice if they'd stop doing that.

I had the understanding (correct me if I'm wrong) that for 3600 baud systems in order to indicate various things like the talkgroup has an emergency, is in a patch group, etc., that the talkgroup 16 uses the range of IDs 17 through 31 for different status bits. Same talkgroup, just indicating all the various status possibilities.

There is an explanation somewhere on this site that states all this more gracefully and probably more accurately than I'm doing.

It isn't the scanner that multiplies by 16 althrough I understand that you need to divide by 16 (convert from decimal to hex and drop the least significant hex character) to program some portable radios.

 

[slicerwizard]

I had the understanding (correct me if I'm wrong) that for 3600 baud systems in order to indicate various things like the talkgroup has an emergency, is in a patch group, etc., that the talkgroup 16 uses the range of IDs 17 through 31 for different status bits. Same talkgroup, just indicating all the various status possibilities.

You've just described how scanners take two separate fields (talkgroup and group status) and combine them for no good reason.
As you said yourself - same talkgroup.

It isn't the scanner that multiplies by 16

It sure is. Talkgroup numbers appear on the control channel for more than just call grants; they show up on affiliations, status messages, dynamic regroup commands, etc. - you know, those OSW's that scanners ignore - and there are no group status bits tacked on to those talkgroup values.

althrough I understand that you need to divide by 16 (convert from decimal to hex and drop the least significant hex character) to program some portable radios.

All Motorola radios are programmed with the real talkgroup numbers (1 to 4000 or so), either in decimal (typically with the leading '8', e.g. TG #1 = 800001) or hex (there's another dumb move - why hex??)

 

[UPMan]

Depends on the system. On true P25 systems (9600 baud control channel) the TG IDs use every one of the 64K numbers with 0 and 65535 reserved for system use. (1 straight through 65534) No dividing by 16 or 32. When UPMan is referring to the IDs being between 2 and 5 numbers in size, how is an id like 1 or 4 or 7 or 9 programmed into a scanner?

From context, the OP was talking about Motorola Type I/II systems, not P25.

For P25 systems (different answer to a different question), oddly enough you would enter 1-digit IDs by entering the single digit.