FDMA or TDMA?
Somerset County 700 MHZ?
- Thread starter rr60
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FDMA or TDMA?
I'm scanning the 700 (i.e. Site 4) on my 996XT and I am frequently seeing it pause on TGID 0x0BBB, which corresponds to Franklin Township Police Dispatch. It is encrypted (naturally), but it's definitely being simulcast on sites 2 and 4.
Here's some of the formatted CC output from my 996XT:
Here's some of the formatted CC output from my 996XT:
It seems to simulcast anything that something is affiliated with (Not necessarily full time). I.E. PD South was simulcasted when a radio was affiliated. Currently, radio 1800000 is affiliated with 3003 (BBB) which is why we're seeing that now....also in FDMA
Somerset County Public Service Radio
Has there been any updates in the system?
Has there been any updates in the system?
robbinsj2
Member
I spent about an hour watching Unitrunker on the 700MHz zone last week. There was a moderate amount of activity, most was on phase 1 channels but Hillsborough PD (whose VHF channel has gone silent) was phase 2. I don't remember now whether the Bridgewater PD talkgroup was phase 1 or 2. Hopefully I'll have more time this coming week to monitor it and gather changes/ updates.
Jim
Jim
StrongSignals
Jim,
I've been monitoring Somerset County (P25) this morning and getting strong signals with three channels. Region 5 & Region 6 and also Police inoperability channel. If this is an example of the quality of transmission, it'll be great! This system went quiet after noon today.
Dave
Jim,
I've been monitoring Somerset County (P25) this morning and getting strong signals with three channels. Region 5 & Region 6 and also Police inoperability channel. If this is an example of the quality of transmission, it'll be great! This system went quiet after noon today.
Dave
I've seen FDMA activity for Bridgewater, but it's not a full simulcast.
I know the county is also trying to accelerate building on the Pill Hill landfill in Bernards township, which would include all bands.
Sent from my SGH-T989 using Tapatalk
I know the county is also trying to accelerate building on the Pill Hill landfill in Bernards township, which would include all bands.
Sent from my SGH-T989 using Tapatalk
Bridgewater PD
Today, I received Bridgewater PD on the Apco 25 Region 10 channel.
Today, I received Bridgewater PD on the Apco 25 Region 10 channel.
It happens when a certain radio affiliates with the system in FDMA mode. It mainly remains simulcast in TDMA mode, but it is there. If you had a TDMA-capable scanner, you'd see it much more frequently.
TDMA capable
I have a APCO25 Phase 1 and 2 scanner. TDMA modulation which can ONLY be monitored using a P25 Phase II compatible scanner. That is If I understand this correctly. Thanks for the information.
I have a APCO25 Phase 1 and 2 scanner. TDMA modulation which can ONLY be monitored using a P25 Phase II compatible scanner. That is If I understand this correctly. Thanks for the information.
Yes, that's correct. As far as I've seen, PD Region 10 has only been online on system site 4 (i.e. the 700MHz system we're talking about here). It operates in a mixed-mode of phase 1 and 2, which is normal for compatibility purposes. We just tend to see Region 10 mostly in Phase 2 (i.e. TDMA) mode. I know Region 7 is full-time TDMA with no simulcast, but if for some reason a radio were to affiliate with Region 7 in Phase 1 mode, we'd hear it again on non-Phase 2 scanners for a period of time.
I'm slowly working my way up to purchasing a 536HP myself to replace my 996XT feed. It's just so expensive to justify the purpose to hear a only a couple more talkgroups.
The BCD536HP is well worth the investment, in my opinion. It's more sensitive than most Uniden scanners I've tested. Although never had the chance with the 996XT, but programming that would be close to impossible for me.That's the best part of the 536HP, just get use to the computer programming and your set.
The 536HP is as close to the AOR AR8600 for sensitivity, than anything else I've seen.
Thanks, again.
The 536HP is as close to the AOR AR8600 for sensitivity, than anything else I've seen.
Thanks, again.
You're tempting me that much more, haha. I really do want it and I've heard of the markedly improved performance it has over anything else out there. Soon, I hope.
And no problem!
No, the database is wrong. The only thing full time TDMA seems to be PD Reg 7 with Ops1 and Ops2 (Ops2 is encrypted). The Bridgewater Patch is on and off FDMA/TDMA and on the rarest occasion OEM REMU goes TDMA (and encrypted once in a while). Everything else should still be listed as FDMA.
I thought so. That's why I worried when I saw W2GLD work a submission he had no way of confirming...
The T only means that it's a TDMA capable talkgroup as the system buildout continues.
A is analog only
D is digital only
I set them to T because this system is a Phase II system and several talkgroups are capable.
A is analog only
D is digital only
I set them to T because this system is a Phase II system and several talkgroups are capable.
I disagree with the idea that T in the database should mean TDMA capable. It's a Phase II system...all talkgroups are therefore technically Phase II capable.
If we're listing A as Analog only and D as Digital only, then T should be TDMA only to avoid further confusion. This way people that do not yet have TDMA capable scanners know whether their scanner will be able to receive the specific talkgroups they want to listen to.
With the newer scanner relying on downloading of the data stored in the database, we cannot afford someone making assumptions and changes without the ability to verify the data.
If we're listing A as Analog only and D as Digital only, then T should be TDMA only to avoid further confusion. This way people that do not yet have TDMA capable scanners know whether their scanner will be able to receive the specific talkgroups they want to listen to.
With the newer scanner relying on downloading of the data stored in the database, we cannot afford someone making assumptions and changes without the ability to verify the data.
Per section 6.3.5.1 of the handbook:
Talkgroups should be listed as to how they are actually being used, not what they are capable of.
Talkgroups should be listed as to how they are actually being used, not what they are capable of.
Not that I disagree with the handbook, because I completely agree, but the database mouseover text for "Mode" contradicts this. Place the cursor over "mode" and T states that it's a "TDMA Capable Talkgroup", NOT a "TDMA-Only Talkgroup" as the handbook would suggest here.
I think this needs to be forwarded to the higher-ups to change that hovertext and avoid confusion. Obviously, TDMA is digital as much as FDMA is and T should be reserved for TDMA-Only. Although, honestly, I think the T should just be removed completely. The scanner's CC decoding will determine FDMA vs TDMA if I'm not mistaken; labeling it at such in the database is just superfluous information.
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