Driver Location Signs

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Re: Driver Location Signs

Post by Steven » Thu Sep 26, 2019 07:26

DanT97 wrote:
Thu Sep 26, 2019 01:04
Doesn’t anyone want to help me get these signs installed in Scotland?
SABRE is not a campaigning organisation.

I suggest you write to Transport Scotland and get the official response from them, outlining their benefits.
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Re: Driver Location Signs

Post by FosseWay » Thu Sep 26, 2019 11:52

On the phone location issue: When using my phone's GPS to track hikes and cycle rides, I often find that the trace is notably divergent from reality, and this problem increases the more obstructions there are between me and the satellites, such as tall buildings, steep-sided cliffs/hillsides and (to a lesser extent) trees. In a dense urban area the effect can be significant enough to place me on a parallel road to my real position, or in the middle of a building and positioned such that an emergency responder may go to the wrong side of the building to find me. If you know where you are - either because you are familiar with the place or because you know where you are with reference to a map - it is always going to be more accurate to give that information than rely on the phone. If you are travelling and have kept an eye on where you are and can pinpoint it precisely on a map, you can do likewise on Google Maps and then read off the coordinates Google provides if you drop a pin there.

I don't have a problem with What3Words as such, but find it to be overly precise. It gives a false sense of precision to quote to 3 square metres if your phone's GPS is only accurate to 10 square metres in the most favourable conditions. It's a bit like saying me confidently stating that the meteorite that killed off the dinosaurs fell 65,000,033 years ago precisely because it says 65 million in a book published in 1986.

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Re: Driver Location Signs

Post by Vierwielen » Mon Oct 07, 2019 12:44

Driver location signs smell of beign a good idea until some politician saw the word "kilometre" in their description and promptly counted out how many vote they would lose to Nigel Farage et al if they promoted the use of DLSs on account of the use of the "K" word. The fact that their use might save lives does nt appear to feasture highly in their priorities.

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Re: Driver Location Signs

Post by Johnathan404 » Mon Oct 07, 2019 15:12

Vierwielen wrote:
Mon Oct 07, 2019 12:44
Driver location signs smell of beign a good idea until some politician saw the word "kilometre" in their description and promptly counted out how many vote they would lose to Nigel Farage et al if they promoted the use of DLSs on account of the use of the "K" word. The fact that their use might save lives does nt appear to feasture highly in their priorities.
I'm not sure that's true. Why does the motorist even need to know what the unit of measurement is? It has no effect on how you use the sign. Most motorways don't start at 0 so the signs won't even tell you how far from the start of the road you are, only where you are.

I'm as sceptical of the Daily Mail as the next person and I don't doubt they might make a story about it, but they make a story about a lot of things and very little of it lasts more than 48 hours.

If politicians were that bothered about "saving lives" as you put it, there would be plenty of ways to get around the issue of the unit of measurement.
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Re: Driver Location Signs

Post by Vierwielen » Mon Oct 07, 2019 18:39

Johnathan404 wrote:
Mon Oct 07, 2019 15:12
Vierwielen wrote:
Mon Oct 07, 2019 12:44
Driver location signs smell of beign a good idea until some politician saw the word "kilometre" in their description and promptly counted out how many vote they would lose to Nigel Farage et al if they promoted the use of DLSs on account of the use of the "K" word. The fact that their use might save lives does nt appear to feasture highly in their priorities.
I'm not sure that's true. Why does the motorist even need to know what the unit of measurement is? It has no effect on how you use the sign. Most motorways don't start at 0 so the signs won't even tell you how far from the start of the road you are, only where you are.

I'm as sceptical of the Daily Mail as the next person and I don't doubt they might make a story about it, but they make a story about a lot of things and very little of it lasts more than 48 hours.

If politicians were that bothered about "saving lives" as you put it, there would be plenty of ways to get around the issue of the unit of measurement.
I frequently use driver location signs to log my progress. Both Wikipedia and CBRD give the DLS readings at various junctions and given that value and the current value, I can work out how far I am from the junctiuon and also how long it should take to get there. If you are on a clear road and drive at 120 km/h (75 mph), you cover 2 km per minute.

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Re: Driver Location Signs

Post by RichardA35 » Mon Oct 07, 2019 19:01

Alternatively, the distance to forward destinations is repeated after each junction on a far larger sign so saving the peering through traffic and the mental arithmetic.

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Re: Driver Location Signs

Post by Johnathan404 » Mon Oct 07, 2019 20:11

Vierwielen wrote:
Mon Oct 07, 2019 18:39
I frequently use driver location signs to log my progress. Both Wikipedia and CBRD give the DLS readings at various junctions and given that value and the current value, I can work out how far I am from the junctiuon and also how long it should take to get there. If you are on a clear road and drive at 120 km/h (75 mph), you cover 2 km per minute.
Good for you. But that has nothing to do with "saving lives", so I'm now even more confused about what your concern was.

What's more, the vast majority of motorists don't need to mentally calculate how long it "should" take to get anywhere, because they insist on using a gadget which tells them exactly how long the journey is likely to take. Most people do not care how long it is likely to take to get to the next junction, it is of no relevance to them. You are not going to change that.

So this is a use you have created for DLS that virtually only you use, and you're then saying DLS can't be used to save lives because politicians are worried that metric-haters will find out that one person on SABRE also use DLS to carry out mental arithmetic in metric? Daily Mail readers have the capacity to worry about a lot of things but I don't think that is going to be high on their agenda.

It doesn't make any sense. If you enjoy doing mental metric arithmetic with the information on DLS then good for you. We are a society of people who like doing things our own way. But you don't need to make out that it's some-kind of dark secret that the powerful elite wouldn't approve of, because it isn't.
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Re: Driver Location Signs

Post by Fenlander » Wed Oct 09, 2019 12:39

FosseWay wrote:
Thu Sep 26, 2019 11:52
I don't have a problem with What3Words as such, but find it to be overly precise. It gives a false sense of precision to quote to 3 square metres if your phone's GPS is only accurate to 10 square metres in the most favourable conditions. It's a bit like saying me confidently stating that the meteorite that killed off the dinosaurs fell 65,000,033 years ago precisely because it says 65 million in a book published in 1986.
Yup, giving an exact 3x3 square to the emergency services which could in theory narrow it down to even which lane the emergency is in when your phone could have drifted off to the other side of a motorway several lanes and the entire other carriageway away is not helpful.

On a local level here's the gist of the facebook conversation I saw relating to a road closing accident yesterday on a busy S2:-
OP- Accident, road closed other side of VILLAGE.
Lots of people- where?, which road?, other side from where?
OP- The other side to where you go into the village near the farm with the horses.
Lots of people- north or south?
Another person- I've just driven past, it's blocked half the road, traffic is bad but you can just squeeze past, I'd go the back way if I were you.
OP- Going north
Lots of people- It's closed going north from the village or closed going north into the village?
OP- It wasn't closed when I went past but looked like it might be soon.
Lots of people- sod it, I'm going the back way regardless to pick the kids up from school.
3rd person- Lots of traffic coming down my sideroad, is the main road closed?
4th person- Wasn't when I just came past
Lots of people- Well that was a waste of time, set off early, went the back way, got stuck in traffic down the back way then arrived only to be told the road was open the whole time.

An hour later the police tweeted they were closing the road for half an hour to allow recovery of a vehicle from a ditch, half hour later there were many comments stating recovery had already taken place with only one lane blocked for about 10mins.

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Re: Driver Location Signs

Post by Vierwielen » Wed Oct 09, 2019 19:44

Johnathan404 wrote:
Mon Oct 07, 2019 20:11
Vierwielen wrote:
Mon Oct 07, 2019 18:39
I frequently use driver location signs to log my progress. Both Wikipedia and CBRD give the DLS readings at various junctions and given that value and the current value, I can work out how far I am from the junctiuon and also how long it should take to get there. If you are on a clear road and drive at 120 km/h (75 mph), you cover 2 km per minute.
Good for you. But that has nothing to do with "saving lives", so I'm now even more confused about what your concern was.

What's more, the vast majority of motorists don't need to mentally calculate how long it "should" take to get anywhere, because they insist on using a gadget which tells them exactly how long the journey is likely to take. Most people do not care how long it is likely to take to get to the next junction, it is of no relevance to them. You are not going to change that.

So this is a use you have created for DLS that virtually only you use, and you're then saying DLS can't be used to save lives because politicians are worried that metric-haters will find out that one person on SABRE also use DLS to carry out mental arithmetic in metric? Daily Mail readers have the capacity to worry about a lot of things but I don't think that is going to be high on their agenda.

It doesn't make any sense. If you enjoy doing mental metric arithmetic with the information on DLS then good for you. We are a society of people who like doing things our own way. But you don't need to make out that it's some-kind of dark secret that the powerful elite wouldn't approve of, because it isn't.
An example that I had in mind is described here. After an accident on the M5, Devon and Somerset Fire and Rescue received a number of calls, but some were so vague (or plainly incorrect) that they did not know whether there was one accident or two, or which lanes were affected or even where the accident was. As a result emergeny services from four different locatiosn were mobilised in order to deal with an incident (or incidents) along a 40 mile stretch of motorway. This meant that resources that might have been needed elsewhere were tied up.

In 2001/2, I worked in Italy where they also have a form of driver location signs on their equivalent of "A" Roads. (See here for the 19 km marker on the SS4). These signs seem to be so ingrained into the Italian way of life, that advertisers use them to direct motorists to their restaurants or garages (eg "XYZ Restaurant on SS4; km 17.2"). If this sort of use of locations signs had been ingrained into the British way of life, then the Devon and Somerset Fire Rescue Service would have known exactly where the incident was.

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Re: Driver Location Signs

Post by Vierwielen » Wed Oct 09, 2019 19:50

Johnathan404 wrote:
Mon Oct 07, 2019 20:11
We are a society of people who like doing things our own way. But you don't need to make out that it's some-kind of dark secret that the powerful elite wouldn't approve of, because it isn't.
I am not sure that I agree with you.

I arrived in the UK from South Africa in 1978. A few years previously I had received a South African Identity Document. My number had 13 or so digits. A note came with the document explaining the meaning of each digit - 6 digits for date of birth, 4 digits for sequence number (0000 to 4999 for males, 5000 to 9999 for females), one digit to denote your race, one to denote whether or not you were a South African citizen and a check digit. In contrast, when I got my British driving licence (the old green type), I could cut off the bottom right hand corner if I did not want my date of birth to appear on my licence, even though it was encoded into my licence number, but they were not telling me that.

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Re: Driver Location Signs

Post by WHBM » Thu Oct 10, 2019 07:25

Johnathan404 wrote:
Mon Oct 07, 2019 15:12
Vierwielen wrote:
Mon Oct 07, 2019 12:44
Driver location signs smell of beign a good idea until some politician saw the word "kilometre" in their description and promptly counted out how many vote they would lose to Nigel Farage et al if they promoted the use of DLSs on account of the use of the "K" word. The fact that their use might save lives does nt appear to feasture highly in their priorities.
I'm not sure that's true. Why does the motorist even need to know what the unit of measurement is? It has no effect on how you use the sign. Most motorways don't start at 0 so the signs won't even tell you how far from the start of the road you are, only where you are.

I'm as sceptical of the Daily Mail as the next person and I don't doubt they might make a story about it, but they make a story about a lot of things and very little of it lasts more than 48 hours.

If politicians were that bothered about "saving lives" as you put it, there would be plenty of ways to get around the issue of the unit of measurement.
Ah, but it's true.

I've told this one before but at university in the 1970s we had a visiting lecture from an official from the MoT, who had been there when motorway junctions were first numbered some years before.

The original plan was to number them based on mileage from a start point, which for roads from London was from the centre. So on the M4 it started at J7 at Chiswick, J9 at Isleworth, J14 at Hounslow, J190 at Llanelli, etc. This had the advantages that you knew the distance between junctions, how far to go, any new junctions readily slotted in, and intermediate mile signs were possible as well. A full plan was prepared and sent to the minister for approval.

The minister said that metrication was government policy, they would be ridiculed if they introduced a new mile-based scheme today, etc. So No.

The team then redid all the plans in kilometres, and sent them up for approval again.

Meanwhile, government reshuffle, minister had changed. New minister said public didn't like kilometres, felt they were being forced on them, they would be ridiculed, etc. So No.

Team hacked off by now, rather grumpily redid them all again based on sequential numbering. And that's how we got what we have got. If the story had got to the Yes Minister scriptwriters I'm sure they could have worked it in.

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Re: Driver Location Signs

Post by Vierwielen » Thu Oct 10, 2019 14:32

At least this is better than what the Italians do - they name all their autostrade junctions and number the bridges over them.

I have often wondered whether or not it would make sense to number our motorway services by referncing the closest location marker value - eg Winchester Services would be "Winchester Services (S96)" while places like South Mimms would have two numbers, depending on the motorway (and only that motorway designation would appear on that motorway's roadsigns).

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Re: Driver Location Signs

Post by jervi » Sun Jan 05, 2020 13:36

So I had a thought about DLS just now, and instead of starting a new thread I'll just use this one.

Why do some roads have multiple datum points? Especially since some of them should be avoidable.
So the most extreme example of this I can think of is the A1, which is expected as it's used many alignements of varying quality.
Here are some example from along the A1 (and A1(M)).
*A1(M) Just north of the M25 (24.2) - which I measured to be 24.9 km from the A501 - makes sense.
*A1 beside the New A14 (3.6). Why did they use another new start point!, and there is no way to distinguish it from other 3.6 markers.
*A1(M) Just North of M1 Junction (56.1), 56 was likely measured from the start of the A1(M) section at Blyth as that is roughly 56km away, although there is a section of A1 between those parts of the A1(M). The A1(M) between Blyth and Doncaster don't have DLS
*A1(M) Just North of Catterick (129.8), it is 125KM north Blyth, so I don't know where those 5KM have disappeared to, however makes sense.
*A1(M) Beside Darlington (9/0 D), now what is going on here! I'm guessing it's using miles, chains or some other imperial measurement?

Since DLS are fairly new (2007 according to the wiki & 2008 according to wikipedia), why couldn't they just use one unit exclusively, whether it being Miles or KM. As far as I am aware, a lot of motorways are measured in imperial for technical stuff, which is reflected by the smaller location posts you find, however on the same bit of road, KMs are sometimes used for DLS.
Also I've noted that newer roads like the A421 (M1->BlackCat) use KM on its marker posts, measuring from the same place as DLS do.

So the M23 starts at 27 km at junction 7 (its Northern Terminus), however it was only ever planned to go about 18 KM further North into London, why would its 0 point be 1/2 further than it needs to be? Also when the M23 turns into the A23, why does the A23 count from Brighton? Surely it would just make sense to carry on counting from the M23. Hopefully if/when the M23 extends down the A23, they will count from London to keep it consistent.
J11 roadwork signage plans showing distances. I measured the distance between 24/8 and 25/7 on the A23 being 881metres/0.55mi/2890ft apart. Which equates the first number being a half-mile and the second number being a tenth of a half mile (or a 1/20th of a mile). Is this common on the rest of the network? and why use half-miles and a fraction of that, why not just use full miles, chains and furlongs?

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Re: Driver Location Signs

Post by RichardA35 » Sun Jan 05, 2020 14:58

jervi wrote:
Sun Jan 05, 2020 13:36
So I had a thought about DLS just now, and instead of starting a new thread I'll just use this one.

Why do some roads have multiple datum points? Especially since some of them should be avoidable.
I'll try to give you a helpful response based upon experience of working in the industry. If people disagree, it would be helpful if they could cite factual backup evidence.
There is no "grand design". Different parts of routes were upgraded at different times by different authorities and consultants using different datum points.
jervi wrote:
Sun Jan 05, 2020 13:36
So the most extreme example of this I can think of is the A1, which is expected as it's used many alignements of varying quality.
Here are some example from along the A1 (and A1(M)).
*A1(M) Just north of the M25 (24.2) - which I measured to be 24.9 km from the A501 - makes sense.
There is no "grand design" at play however
jervi wrote:
Sun Jan 05, 2020 13:36
*A1 beside the New A14 (3.6). Why did they use another new start point!, and there is no way to distinguish it from other 3.6 markers.
*A1(M) Just North of M1 Junction (56.1), 56 was likely measured from the start of the A1(M) section at Blyth as that is roughly 56km away, although there is a section of A1 between those parts of the A1(M). The A1(M) between Blyth and Doncaster don't have DLS
*A1(M) Just North of Catterick (129.8), it is 125KM north Blyth, so I don't know where those 5KM have disappeared to, however makes sense.
There is still no "grand design". Different parts of routes were upgraded at different times by different authorities and consultants using different datum points.
jervi wrote:
Sun Jan 05, 2020 13:36
*A1(M) Beside Darlington (9/0 D), now what is going on here! I'm guessing it's using miles, chains or some other imperial measurement?
No all in metric - someone has used the shorthand of the marker post numbering when designing the sign using 9/0 instead of 9.0
jervi wrote:
Sun Jan 05, 2020 13:36
Since DLS are fairly new (2007 according to the wiki & 2008 according to wikipedia), why couldn't they just use one unit exclusively, whether it being Miles or KM. As far as I am aware, a lot of motorways are measured in imperial for technical stuff, which is reflected by the smaller location posts you find, however on the same bit of road, KMs are sometimes used for DLS.
No - in my experience everything is metric
jervi wrote:
Sun Jan 05, 2020 13:36
Also I've noted that newer roads like the A421 (M1->BlackCat) use KM on its marker posts, measuring from the same place as DLS do.
A new route = a new datum
jervi wrote:
Sun Jan 05, 2020 13:36
So the M23 starts at 27 km at junction 7 (its Northern Terminus), however it was only ever planned to go about 18 KM further North into London, why would its 0 point be 1/2 further than it needs to be? Also when the M23 turns into the A23, why does the A23 count from Brighton? Surely it would just make sense to carry on counting from the M23. Hopefully if/when the M23 extends down the A23, they will count from London to keep it consistent.
jervi wrote:
Sun Jan 05, 2020 13:36
J11 roadwork signage plans showing distances. I measured the distance between 24/8 and 25/7 on the A23 being 881metres/0.55mi/2890ft apart. Which equates the first number being a half-mile and the second number being a tenth of a half mile (or a 1/20th of a mile). Is this common on the rest of the network? and why use half-miles and a fraction of that, why not just use full miles, chains and furlongs?
The M23 was designed as a single route from London to Crawley in metric and the datum point was set somewhere just south of Streatham High Road near Streatham station for convenience.

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Re: Driver Location Signs

Post by jervi » Sun Jan 05, 2020 21:21

Okay, thanks for answering my questions, but still have more :)

While I understand that different upgrades at different times can cause the length of route to change, so the datum point for each section may make it easier to manage that section of road, however for DLS, since they are newer than these old datum points that were primarily made for maintenance. Why couldn't they of all used one new datum point for DLS. Like on the D2 A46, both south and north of Newark have marker posts measured in KM. Newark is S2 with no marker posts. However I've noted they have allocated about 1km in slack (in addition to the length of the current route), so if a new DC bypass was longer than the current bypass, it wouldn't have to re-use the same marker numbers or botch something else in, if anything the distances might skip a KM.

Also IAN 093 10 states at point 2.7.3 that
The information shown on a driver location sign must always be uniquecompared to other driver location signs, to minimise confusion following the reporting of an incident or defect. This means that a national distance referencing system should be used on driver location signs and distance marker posts along a route, i.e. the distance shown must be unique for the route, if the concept of driver location signs is to be a success. It is recommended that adjacent area teams and DBFO teams along a route should liaise to ensure that there is no
duplication of distance information on distance marker posts and driver location signs along a route.
For the avoidance of doubt, this means that there must never be the same legend shown on driver location signs at different locations.
So maybe that is what the "D" is for at the end of A1(M) near Darlington? So it makes that section is unique, even if other parts of the A1 use the same kilometerage?
However, suppose North of Blyth gets DLS signs, since that's a datum point for A1(M) between ~J43 to ~53 you would expect that signs immediately north of Blyth junction would start from 0. Meaning that It would be duplicate of those on the A1 at Huntingdon (if it becomes the A1(M)).
Or if A1(M) Peterborough - Alconbury got DLS, then you would have the same A1(M) 24.2 sign as the one just north of the M25 junction, if it uses the same datum point as the A1 beside the A14.

I was thinking a bit harder, and I think I worked out why there are four datum points (at-least signed). Maybe, due to the uncertainty of the distances of the A1 in the future (due to upgrades), they set new points at the end of each uncertain section (Non-Motorway that were around in 2008). These sections would of been:
*A501 (Northern Circular) -> A14 - section "A" - 99.95km (on current northbound alignment)
*A14 -> J34 (Blyth) - section "B" - 142.75km (on current northbound alignment)
*J34 -> J56 - section "C" - 139.1 km
*J56 - ??? - section "D"
*??? - ??? - section "E" - as more isolated section are built to motorway/expressway standard

This would mean that any major shifts in the routes length would have a limited impact on the DLS. So far, section D signs were fabricated with the letter on them, but not the other ones because they would not be duplicates (at the moment). Although the A1(M) J40 hasn't been given a new datum point, potentially they expect the A1 upgrade here to not affect the length a noticeable amount (new road may even be shorter).

About the M23 datum point, at Junction 7 it has 27km on the marker posts, however it is 17.7km (direct line) to the North side of Tooting Bec Common (the most Northern Point it was ever meant to be). Yes it wouldn't be a straight line, but that wouldn't add 10km. Again, the only thing I can think of is if they allocated an additional 5-8 KM additional on its northern end, if in some unlikely turn of events, the motorway would of been extended beyond the Thames?

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Re: Driver Location Signs

Post by avtur » Sun Jan 05, 2020 22:43

Vierwielen wrote:
Wed Oct 09, 2019 19:50
.... when I got my British driving licence (the old green type), I could cut off the bottom right hand corner if I did not want my date of birth to appear on my licence, even though it was encoded into my licence number, but they were not telling me that....
The formatting of the driver's number has never been a secret.

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Re: Driver Location Signs

Post by JohnnyMo » Mon Jan 06, 2020 08:01

avtur wrote:
Sun Jan 05, 2020 22:43
Vierwielen wrote:
Wed Oct 09, 2019 19:50
.... when I got my British driving licence (the old green type), I could cut off the bottom right hand corner if I did not want my date of birth to appear on my licence, even though it was encoded into my licence number, but they were not telling me that....
The formatting of the driver's number has never been a secret.
I remember that being explained when I was about 14 in Computer Studies, I then spotted the encoding used was ambiguous. Two different dates of birth could give the same number.

I can't now remember the algorithm used.
Johnny Mo

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Re: Driver Location Signs

Post by JohnnyMo » Mon Jan 06, 2020 13:07

jervi wrote:
Sun Jan 05, 2020 21:21
...
I was thinking a bit harder, and I think I worked out why there are four datum points (at-least signed). Maybe, due to the uncertainty of the distances of the A1 in the future (due to upgrades), they set new points at the end of each uncertain section (Non-Motorway that were around in 2008). These sections would of been:
*A501 (Northern Circular) -> A14 - section "A" - 99.95km (on current northbound alignment)
*A14 -> J34 (Blyth) - section "B" - 142.75km (on current northbound alignment)
*J34 -> J56 - section "C" - 139.1 km
*J56 - ??? - section "D"
*??? - ??? - section "E" - as more isolated section are built to motorway/expressway standard
...
DLS were originally only on motorways, 100m posts giving direction to the nearest emergency phone.
So when the A1(M) was 3 motorways (Hertfordshire, Doncaster By-Pass & Durham). The Bedfordshire & North Yorkshire sections had been upgraded to dual carriageway in the 50’s. So little prospect of future upgrade joining these section. There was no plans to extend the motorway south from the Doncaster By-pass. If there was then I expect the Blyth bypass would have been included in the A1(M) as this was the same specification as the Doncaster Bypass complete with hard shoulders.

Therefore there was no problem with 3 datum points, as each section of motorway was controlled by a different control centre, in fact it made sense as it kept the numbers manageable.

It is now a problem with mobile phones and national call centres where duplicate DLS can be problematic.

I can remember the A1 in Yorkshire used the Huntingdon datum point not Blyth, however as these sections were upgraded to motorway the datum point was changed to Blyth.
I have always assumed the D was for Durham.
Are there any DLS on the A1 north of Newcastle?
Johnny Mo

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Re: Driver Location Signs

Post by Ruperts Trooper » Mon Jan 06, 2020 13:48

JohnnyMo wrote:
Mon Jan 06, 2020 08:01
avtur wrote:
Sun Jan 05, 2020 22:43
Vierwielen wrote:
Wed Oct 09, 2019 19:50
.... when I got my British driving licence (the old green type), I could cut off the bottom right hand corner if I did not want my date of birth to appear on my licence, even though it was encoded into my licence number, but they were not telling me that....
The formatting of the driver's number has never been a secret.
I remember that being explained when I was about 14 in Computer Studies, I then spotted the encoding used was ambiguous. Two different dates of birth could give the same number.

I can't now remember the algorithm used.
How so ?

Position 9-10 is Day, 7-8 is Month (+50 for females), 6 is Decade and 11 is Year - the only possible ambiguity is for drivers over 117 years of age!
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Re: Driver Location Signs

Post by jervi » Mon Jan 06, 2020 17:45

JohnnyMo wrote:
Mon Jan 06, 2020 13:07
It is now a problem with mobile phones and national call centres where duplicate DLS can be problematic.

I can remember the A1 in Yorkshire used the Huntingdon datum point not Blyth, however as these sections were upgraded to motorway the datum point was changed to Blyth.
I have always assumed the D was for Durham.
Are there any DLS on the A1 north of Newcastle?
I've spent ages on GSV trying to find NLS as well as marker posts, and anything North of the A1(M) is hard to find any marker posts. I couldn't find any.

Also, after a google search, I found that people were talking about this exact thing in 2010. Thread here, which you were part of Johnny ;)

However, after looking at the marker posts on the A1(M) Alconbury to Peterborough, they have a 0 marker post there, as well as the other 0 marker post of the new A1 Alignment beside the A14. So there are two 0 marker points within 8km of each other, this may lead to another section that may throw off the "D" from the 4th section (if the D meant 4th as it would become the 5th).

What I've read on this thread says that some roads have a damun point above 0, meaning that expanding towards London (or anti-clockwise) would not result in a negative number (such as the new A1 beside the A14 if it used the same datum point as the A1(M) to the north). In hindsight that's what they should of done for the A1(M) Alconbury to Peterborough section, especially if at that stage the A14 Hunting bypass & A421 / A428 projects were at least a small idea that would of resulted in the A1(M) extending south.

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