I just came across a note on the TxWARN P25 page stating that some of the TGs are Phase II digital. Which ones?
Phase II on TxWARN P25?
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I saw that too. There have been recent references to TDMA here: http://groups.yahoo.com/group/HoustonScan/
Using the "Search" window below the HoustonScan logo, you can type in "TDMA" and find them. And, there will probably be more info about this coming soon (unfortunately).
Using the "Search" window below the HoustonScan logo, you can type in "TDMA" and find them. And, there will probably be more info about this coming soon (unfortunately).
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Time to speed up development on those Phase II scanners, wink, wink.
Considering that Houston's also building a Phase II system, UPMan better do something soon before he has every wrecker driver in Harris County demanding to talk to him!
To recap what the HoustonScan thread says, it appears that the radio shop and a few DPS talkgroups are showing as TDMA talkgroups.
What Radio Shop TGID are you referring to? I was picking up 1285 yesterday around here.
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Keep in mind that only the APX series radios will do Phase II or X2 TDMA. Everybody that uses XTS/XTL series radios will operate in normal Phase I FDMA mode. Furthermore, the zone controller can dynamically control whether FDMA channels or TDMA timeslots are allocated to a talkgroup based on who's affiliated to that talkgroup; in a nutshell if a user with an XTS series radio switches to a talkgroup that has APX radios already on it the system will force everyone to use FDMA. So don't start tossing those shiny new 396/996XTs just yet. 
Keep in mind that only the APX series radios will do Phase II or X2 TDMA. Everybody that uses XTS/XTL series radios will operate in normal Phase I FDMA mode. Furthermore, the zone controller can dynamically control whether FDMA channels or TDMA timeslots are allocated to a talkgroup based on who's affiliated to that talkgroup; in a nutshell if a user with an XTS series radio switches to a talkgroup that has APX radios already on it the system will force everyone to use FDMA. So don't start tossing those shiny new 396/996XTs just yet.
Thanks for clearing that up. Knowing that most users on the system are using either XTS2500s, 3000s, or 5000s, it'll probably be a while yet before the APXs begin making an appearance big enough to warrant full-time Phase II. Come to think of it, I've never actually seen anyone using an APX in person.
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No 3000s, just Astro25 products (2500/5000/1500 etc.) 3000s support rebanding and Astro25 9600 trunking but not 700 MHz.
All of the radio techs have VHF/700/800 APX handhelds, as do a bunch of the east Harris County volunteer fire departments (Channelview, Cloverleaf, etc.) and Montgomery County VFDs. I wouldn't be surprised if DPS has them now too, though historically they have almost never carried handheld radios.
Really? I didn't know that. Anyway, why are those east Harris County VFDs using the APXs? I though they were just VHF or UHF conventional.
While we're adding to the wish list, I'd like something that handles simulcast systems better (I'm assuming simulcast issues will still be present along with TDMA?). I'm planning to get a yagi and see if that helps any.
Im not the smartest cookie in the jar but i looked up "Houston" "Harris" Co 700 simulcast system, then checked it on the FCC license and all the "emission' designators still point to "Phase1 C4FM and P25 Linear Simulcast Mod Astro, this is if im reading it correct acording to the "emission chart in Wiki??....
It is, for the time being, apparently. However, the City of Houston is currently well along in their progress with their own, separate 700 system, which WILL be Phase II, and is slated to be in service sometime next year or so.
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