From The RadioReference Wiki
Revision as of 10:58, 17 May 2013 by Loumaag
Scratch page for me
Houston Police and Fire P25
The Houston Police (HPD) and Houston Fire (HFD) departments have made the switch to digital TDMA technology.
In April and May of 2013 the Houston Fire department and then the Houston Police department abandoned the use of their respective legacy UHF analog conventional systems and moved to the TxWARN P25 system. This move, in addition to moving from an analog conventional system to a digital trunking system caused problems since HPD and HFD are using P25 Phase 2 technology.
The City of Houston recognized that this move would cause problems for various interest that monitor those agencies and as a partial aid to those interests, including the scanner hobbyist, the dispatch channels for HPD and the main dispatch channel as well as 4 regional channels for HFD are being simulcast on P25 Phase 1 talk groups, allowing for normal P25 trunking capable scanners to monitor those channels.
In addition to the move to P25 Phase 2 technology, both HPD and HFD are making extensive use of encryption on all tactical (Tac) and talk around (TAC) channels. The reasoning for this is not within the scope of this discussion; however, it should be noted that their decision to leave non Tac and TAC channel in the clear is to everyone's advantage. As this article is being prepared, there is only one scanner available (the GRE PSR800) that is capable of monitoring P25 Phase 2 channels, and that unit is no longer in production.
This brings this discussion to the simulcast of the dispatch channels and regional channels (for HFD) in P25 Phase 1 technology and how that can be implemented in a normal P25 trunking scanner.
Specific Talk Groups
The HPD has identified 12 channels and HFD has 5 to rebroadcast in P25 Phase 1, they refer to these as Mutual Aid channels as any authorized user can access these to communicate with them:
- HPD -- These cover the basic 12 dispatch / common use channels they had on the legacy analog conventional system minus the old car to car channel (Channel 8) which is not available any longer
- TG 30180 - HPD North MA -- North Dispatch; also known as North Shepard
- TG 30181 - HPD NEast MA -- North East Dispatch; also know as Kingwood
- TG 30182 - HPD SEast MA -- South East Dispatch
- TG 30183 - HPD SWest MA -- South West Dispatch; also known as Beechnut
- TG 30184 - HPD Cntrl MA -- Central Dispatch
- TG 30185 - HPD SCtrl MA -- South Central Dispatch
- TG 30186 - HPD NWest MA -- North West Dispatch
- TG 30187 - HPD West MA -- West Dispatch; also known as Westside
- TG 30188 - HPD Sp Op MA -- Special Operations Dispatch; traffic dispatch; used to be Channel 7 on the legacy lineup
- TG 30189 - HPD Detct MA -- Detective Dispatch; hasn't been used for detectives for a long time; used to be Channel 10 on the legacy lineup
- TG 30190 - HPD CtyWd MA -- Citywide Dispatch; a common use dispatch monitored channel used for wide events
- TG 30191 - HPD AIrprtMA -- Airports Dispatch; common use for airports around the city
- HFD -- These cover the dispatch channel and four quadrant regional channels. The Tac channels that were previously used are no longer available, even as direct equivalents to the legacy analog conventional channels and all Tac channels are encrypted in any case.
- TG 40002 - HFD Disp MA -- Robot dispatcher, backed up by live dispatcher who can be contacted and occasionally calls individual units on this talk group
- TG 40018 - HFD NE RO MA -- North East Regional Operator - This and the following three channels are used for communication back to dispatch office on a regional basis. They have not, so far been used in working a fire; although, responding units occasionally will ask questions or receive direction on these.
- TG 40038 - HFD SE RO MA -- South East Regional Operator
- TG 40058 - HFD NW RO MA -- North West Regional Operator
- TG 40078 - HFD SW RO MA -- South West Regional Operator
- Other -- There is at least one more P25 Phase 1 channel available at this time, although of limited interest
- TG 45191 - Hou Parking1 -- Houston Parking Enforcement channel
To receive the above talk groups, a scanner must be programmed with a specific site and, depending on your scanner's make up, as a separate system.