Robert Woolley wrote:
On Thu, 14 Aug 2003 23:09:24 +0100, David Cowie
wrote:


They look like cameras. Think on the side is printer FB Detection
(FireBrigade?). Are they testing to see if there are any cars at the
lights before turning red ? These lights do seem particularly short if
there are no cars and I'm on bicycle attempting to get to them before
turning amber.

Any ideas on how they work or how to make them work for me ?


They are detectors which use microwaves to 'see traffic' and adjust
accordingly. Microwaves get reflected by moving metal objects. They
don't work well if traffic is generally very slow moving.

Microwave detectors are replacing inductive loop detectors.
Lets get the baco foil out and have some fun :-)

On Fri, 15 Aug 2003 01:01:40 GMT, Chris p
wrote:

Robert Woolley wrote:
On Thu, 14 Aug 2003 23:09:24 +0100, David Cowie
wrote:


They look like cameras. Think on the side is printer FB Detection
(FireBrigade?). Are they testing to see if there are any cars at the
lights before turning red ? These lights do seem particularly short if
there are no cars and I'm on bicycle attempting to get to them before
turning amber.

Any ideas on how they work or how to make them work for me ?


They are detectors which use microwaves to 'see traffic' and adjust
accordingly. Microwaves get reflected by moving metal objects. They
don't work well if traffic is generally very slow moving.

Microwave detectors are replacing inductive loop detectors.

Lets get the baco foil out and have some fun :-)

Seems that might be the only way I can get the light to change ! How
about a foil vest

Bit annoying waiting at the light (for it to change) knowing that
there's no way to activate a sensor and wait for a car to approach
before it'll change.

BTW the location is Surbiton. These sensors have a connecting wire
into the top of the light behind the red light.

gone are the days of laying a bike down in the road over the sensor

Following on from David Cowie's message. . .

Seems that might be the only way I can get the light to change ! How
about a foil vest

Bit annoying waiting at the light (for it to change) knowing that
there's no way to activate a sensor and wait for a car to approach
before it'll change.

They are _speed_ sensitive with a cut-off at about 15mph. Complain to
the appropriate highway authority who should be able to tweak it to
cotton on to your approach..

gone are the days of laying a bike down in the road over the sensor


--
PETER FOX Not the same since the pancake business flopped
2 Tees Close, Witham, Essex.
Gravity beer in Essex http://www.eminent.demon.co.uk

In article ,
(Peter Fox) wrote:

[Microwave traffic light detectors]
They are _speed_ sensitive with a cut-off at about 15mph.

Do you have evidence for that speed cut-off? They have been used for
detecting pedestrians at puffin and toucan crossings for some time.

--
Colin Rosenstiel