Hi there,
Just give you an insight about Emergency Comms in the UK.
Prior to 2004, the Police used to use both VHF and UHF.
VHF radios (often made by Cleartone) were fitted to cars and were primarily AM modulation with frequencies between 150.000 and 155.000 mhz. These would be used to talk to the County controller.
Most counties were split into regions. For example North, Central, South each having a county channel used for dispatching Traffic Cars (Motorway), ARV Armed Vehicles and other non. local incidents.
Also used were UHF radios in the 450.0000 to 453.0000 band, both installed in Cars and portables. These would be used to communicate locally, often through one or two linked repeaters to give communications within a town or district.
Portables varied from county to county but usually were either made by Phillips or Motorola set to output 2 Watts.
99 channel Motorola HT600E's (MT1000 clones) were issued from the late eighties and provided a good 10 years service for most counties. Some chose to replace this equipment in the late nineties and most chose MT6000E's (HT1000 in US I think) as the logical replacement. From the early nineties, most counties choose to use speaker mics and these had antenna ports to improve signal coverage.
In the late nineties however, there was allot of speculation about rumours of a digital system being thought about as a UK wide system. This put many counties radio replacement schemes into 'HOLD' as they waited to see the outcome of the rumours. This lead in some cases to some counties using their original HT600E's right up to 2003.
Some counties however, didn't wait and in 1997 Staffordshire County Police set up one of the first large scale Motorola SmartNet systems in the UK. Called StarNet. StarNet was to be a pioneer in grouping both Police, Ambulance and Fire into one system. The VHF system was commissioned and as it progressed, the Ambulance service dropped out of the project shortly after leaving just the Fire service and Police. Portable radios were mostly Moto MTS2000 keypad and non keypad, mobile radios were Moto MCS2000
The Met Police of London commissioned a UHF SmartNet system around the same time using around 15 sites spread over london and its boroughs. Indeed some remaining boroughs are still on the system.
In 2001, the biggest shake up in Emergency Communications for over 30 years was announced. The project called 'Airwave'. Airwave was due to bring all emergency services onto one platform, UHF TETRA. This would allow seamless roaming throughout the whole country. Two manufacturers provide the radios, Motorola has its MTH800 portable and MTM800 mobile radio and Sepura. These radios use 1 watt of output in the 390mhz band.
Police Forces between 2001 and 2006, began to switch with Lancashire Police being the first and London's Met Police being the last. Indeed the Met Police are still rolling out the system in some boroughs.
The Fire Service currently use lowband VHF, some use AM some FM but all are in the 70mhz band. Scottish brigades use 155mhz. All are due to move to Airwave by 2010.
The Ambulance service, which currently uses channels in the 166mhz area will also be switching to Airwave by 2010.
None of the equipment is owned by the Uk Forces, its owned by company O2, formally British Telecom. The users have to buy the radios and then pay for the airtime they use. This rather stupid (in my opinion) implementation has lead to officers in the field to be told not to use their radios too often as it racks up the bill!! No not a joke!
All in all quite a colourful history, and as Airwave is digital encrypted many, many times over, we have no emergency services to listen to! So US, think yourselves lucky!
Class dismissed! Do I get a prize for longest answer to a single question?
Regards
Rich
