General Buying Advice
Speed camera warning and driver safety alert systems now come in five basic forms:-
- Active radar detection.
- Active laser detection.
- GPS location based camera and hazard warning.
- GPS location, plus active laser detection.
- GPS location, plus active radar and laser detection.
Pros and Cons
Each type of device has inherent advantages and disadvantages. for the types stated above, these can generally be summed up as follows:-
- Active radar detection: The traditional radar detector.
The benefits of this type of unit are now seriously limited for two main reasons.
Firstly, as the amount of unrelated electronic hardware by the side of roads has increased, so has the amount of spurious signal likely to cause false triggering of radar detection hardware. Whilst this has been countered to an extent with enhanced discrimination technology, any device of this type is still inherently prone to false triggering. This can often result in the driver switching the unit off, or reducing its sensitivity to such an extent that it becomes largely useless.
Secondly, the actual devices used for speed enforcement are increasingly moving away from radar based speed measurement. As a result, many speed enforcement devices (SPECS, Truvelo, etc) cannot be picked up using a radar detector, as there is no actual radar signal to detect. Recent trends suggest that whis will increasingly be the case in future, to the point where most or all enforcement hardware will produce no detectable emmission.
- Active laser detection.
A few manufacturers now offer laser detection only devices. These work solely by detecting spurious laser signal from handheld or vehicle mounted laser based enforcement equipment. As a result, they will not give any warning of fixed enforcement devices (GATSO, SPECS, Truvelo, etc). False triggering with this type of device is virtually non-existant - however, due to the narrow focussed beam emitted by laser enforcement devices, actual genuine warnings can be relatively unreliable.
- GPS Based location.
GPS based devices work by comparing the vehicle's position against a database of known camera and blackspot locations. This gives highly reliable and accurate information, and most devices have very comprehensive databases. The benefits of this type of device are however limited where mobile enforcement is concerned. Some will use databases which include regular mobile speed check locations, but the number of locations which can be recorded in this manner is obviously limited. False triggering with this type of device is virtually non existant and where it does occur, this is generally due to outdated location data (ie. temporary cameras which have subsequently been removed, etc).
- GPS plus laser.
By far the commonest devices, these combine GPS database comparison with active laser detection. As a result, they can warn the driver about the vast majority of speed enforcement devices, with relatively few exceptions. The only devices which will not be detected are handheld radar guns (increasingly rare) and portable radar devices (mini Gatso, etc). False triggering of this type of device is generally no more common than with GPS only devices.
- GPS, plus radar and laser.
By far the most effective option, these provide advance warning of all current fixed and portable roadside enforcement hardware. GPS blackspot and camera data gives effective warning of virtually all static enforcement hardware, the laser detector provides warning of newer laser based vehicle mounted and handheld devices, and the radar detector gives advance warning of older handheld devices or portable radar based hardware. The only drawback to this type of device is that, as with standalone radar detectors, false triggering can be problematic, particularly in urban areas. Most do however have a simple means by which to temporarily override radar detection in problematic areas.
Which to buy?
With an increasing variety of speed enforcement hardware now being deployed around the UK's road network, generally speaking, GPS based detection is essential to give reasonable advance warning of the main hardware in use. In addition to this, laser detection should probably be considered essential to provide warning of handheld and vehicle mounted devices. By using GPS and laser in combination, advance warning will be provided in the vast majority of cases.
Where absolute maximum coverage is required, GPS and laser should also be combined with active radar detection, however, where this is the case, the user should be aware that this will almost certainly result in false triggering on a regular basis.