GSM WORLD

uk.telecom.mobile readers might remember my recent acquisition of a
Cellnet TrafficLine gadget which picks up TrafficMaster signals and
warns me of traffic congestion nearby. For those who dont know, this
is one of the little gadgets which run on batteries and consists of
one green LED and four red LEDs which upon approaching a TrafficMaster
transmitter, indicate either no problem or the direction of traffic
congestion in the vicinity.

I have found the gadget very useful and easy to use but wonder whether
the sequence of beeps which accompany the LEDs illuminating is
actually indicating the severity of the congestion. Seems strange that
the number of beeps varies.

I guess eventually time will answer this question but if someone could
help me out regarding this query or can direct me to any other
technical information about how the device works, Id appreciate it.

Thanks,
Stuart
http://www.radox.freeserve.co.uk/driving.htm

On Sat, 29 Nov 2003 16:38:52 -0000, Stuart Dalby
wrote:


Yes, IIRC:

One beep, with one red and one green LED: unit waking up, no signal
nearby to report on.

Three beeps = Road (now) clear, sometimes also as a wakeup if the unit
went to sleep between transmitters

Five beeps = trouble ahead, lights can give more info. Intended as a
prompt to call the info line for more detail.

One beep with red, repetition of previous alert at the next
transmitter along the road.


It works like a location-dependent pager, you get signals up to about
400m from the roadside transmitter (range depends on various factors)
give you road status info based on TMs data. I think the data is
valid for about 15miles ahead, an alert means the average speed over
the last 3 minute period has fallen below a threshold which I think is
around 25 mph. TM use a combination of number-plate recognition
cameras and Doppler radar sensors to measure average traffic speeds on
sections of major roads in real time. More info on their website.

The older RAC unit with sets of three two-colour red/amber LEDs for
each compass point can discriminate the delay severity and location
rather better. Red means severe delay - average speed under 15
mph(??); amber means delay - average speed under 25 (??) mph.

HTH.

--
RM

On Sat, 29 Nov 2003 20:32:52 +0000, Rick Marks wrote:


Ive been using one of each of these two sorts for the last few weeks,
but as I rarely drive on main roads at peak times, Ive yet to see
what happens when congestion is reported.

The two units certainly respond to the same signals - the beeps and
the green light arrive at about the same time every time.


--

Iain
the out-of-date hairydog guide to mobile phones
http://www.hairydog.co.uk/cell1.html
Browse now while stocks last!

Rick Marks wrote in message
news:rgvhsvo8v29g8q5mvn88jua10nn1opmsiv@4ax.com...

Thanks for that Rick. Very helpful.

Stuart
http://www.radox.freeserve.co.uk/driving.htm

On Mon, 1 Dec 2003 08:38:17 -0000, Stuart Dalby
wrote:



While looking for something else last night I came across some of the
BT Cellnet (as was) marketing blurb that came with the unit. The
threshold speed for alerts is 30mph and the trouble range is 15
miles or at least 2 motorway junctions ahead.