14/03/2002 - Police reconsider using TETRA

(Revision to the story): We have been told that TETRA vehicle radios have been turned off in Manchester police cars because of their tendency to turn into loud 'squawk boxes' are various times. The loud squawking noise they have been emitting without warning now and again have been causing potentially dangerous incidents as police officers jump to try to quieten the din.

Greater Manchester Police have temporarily "binned" their new TETRA handsets as they have been proving unreliable in field service. Calls either couldn't be made when needed, or would be made and then the link would cease working properly. This meant officers needing to carry both the new TETRA handsets and the older analogue ones. This was leading to some operational difficulties.

As an interim measure the new TETRA handsets have been placed on one side and will not be routinely carried by officers until the suppliers have identified and implemented solutions to make the system work adequately in practice.

The GM Police are confident that their suppliers, led by MMO2 Airwave, will manage to work out how to make their system work effectively, and look forward to being able to use TETRA as envisaged by PITO and the Home Office, at some point in the future.

Powerwatch comment: The MMO2 TETRA system (BTAirwave) is using lower powers in the handsets, the vehicle radios and at the base-stations than TETRA was originally designed for. It is not clear why they are doing this (e.g. 1 watt handsets instead of 3 or 4 watt) other than to minimise any possible adverse health effects due to the 17.6 Hz pulsing bursts of microwaves that are emitted by the handsets, as higher powers would lead to a more robust telecommunications system. It is likely that far more base-stations than first envisioned will be required to make up for the lower powers being used. This is purely our surmise of what may be at least part of the problem.