How to spot an unmarked police car

[spookly]

Big Performance said:

spookly said:

I'm currently building a tetra/airwave detector. Similar to the Python or Target BlueEye.

Built using a Raspberry Pi 3, an SDR and a small LCD screen. Just need to write a python or C++ gui for it and it'll work. I can already scan the relevant frequencies and identify the uplink radio chatter, but until I create an interface I can only see it on a waterfall graph or in raw csv data files.

It isn't breaking the law as the device is incapable of decrypting the traffic, and in this instance is not even capturing encrypted data samples, it simply scans the relevant frequencies several times over 4 seconds then reports back the strongest signal found.

After calibration it should be able to tell you roughly how far the nearest active (ie. switched on) tetra mobile unit is.
I'll set it to display a dB output, but depending on results of calibration I might also create:

• a graph output
• an indicator of whether receive strength is currently rising/falling (ie. likely moving away or towards source)
• number of active channels identified (identify higher/lower number of different sources)
• approximate distance (probably fairly coarse... something like <200m, <500m, <1mile) - this will be indicative only due to lots of factors (reflection, original signal strength, etc)

I already had the RPi 3, and the screen. So total cost is about £25 for a decent shielded SDR. If you wanted to buy all the stuff required on the cheap then you'd be looking at about £60-£70.

I then plan to add a Bluetooth media player, GPS speedo, and possibly add two remote HD cameras to make a dashcam. Will also put it into a case and maybe add battery/ups power.

I expect it to be reasonably useless in urban areas, especially leaving home as I live by a fire stations, and you are never very far from an ambulance, policeman, pcso or fire engine. But it should still show rough distance and whether sources are getting closer or further away.

Edited by spookly on Friday 17th March 10:52

How much to buy one ?

You can buy one from Python detectors for about £250. That uses LEDs to show roughly how far you are from a source. I don't plan on making/selling these as I can't be arsed.

If you want to build your own, then the cheapest you could do it..... about £50.

Hardware: Any cheap DVB TV stick with an R820T2 chipset. Plug that into a Raspberry Pi. Connect a screen for the PI, or connect LEDs for display (even cheaper).

Then all you need to do is install RTL-SDR software on the Pi, and use rtl_power to scan the frequencies and it'll spit out csv formatted data. Then you need to write a python or C++ program to interpret the input and display some output.

[Mandalore]

How do unmarked Police Cars choose their next random victims.

Speed significantly in excess of the other vehicles around them
Inconsiderate (to other motorists) driving.
Erratic driving.
st plates (if only!)
Statistics relating to the model of car, age of driver and time of day.
Other statistics- often called an -ism.


Not getting tugged, whilst still making good progress is incredibly easy.
You just do everything sensible not to stand out from the herd.

[frankenstein12]

Greendubber said:

Are drivers totally void of any responsibility then?

Of course they are responsible. As a rule of thumb its likely that in the scenario of rear enders caused by mobile or fixed speed cam late brakers the person who runs into the back of them is clearly either not maintaining a decent following distance or just not paying attention. It is also fair to blame the idiot panic braking to a ticket.

It does not however change the fact that the speed cameras cause accidents rather than reduce them as they do not teach people to drive safely. All they do is teach people to resent police and to continue to drive like utter pillocks.

[4rephill]

spookly said:

I'm currently building a tetra/airwave detector. Similar to the Python or Target BlueEye.

Built using a Raspberry Pi 3, an SDR and a small LCD screen. Just need to write a python or C++ gui for it and it'll work. I can already scan the relevant frequencies and identify the uplink radio chatter, but until I create an interface I can only see it on a waterfall graph or in raw csv data files.

It isn't breaking the law as the device is incapable of decrypting the traffic, and in this instance is not even capturing encrypted data samples, it simply scans the relevant frequencies several times over 4 seconds then reports back the strongest signal found.

After calibration it should be able to tell you roughly how far the nearest active (ie. switched on) tetra mobile unit is.
I'll set it to display a dB output, but depending on results of calibration I might also create:

• a graph output
• an indicator of whether receive strength is currently rising/falling (ie. likely moving away or towards source)
• number of active channels identified (identify higher/lower number of different sources)
• approximate distance (probably fairly coarse... something like <200m, <500m, <1mile) - this will be indicative only due to lots of factors (reflection, original signal strength, etc)

I already had the RPi 3, and the screen. So total cost is about £25 for a decent shielded SDR. If you wanted to buy all the stuff required on the cheap then you'd be looking at about £60-£70.

I then plan to add a Bluetooth media player, GPS speedo, and possibly add two remote HD cameras to make a dashcam. Will also put it into a case and maybe add battery/ups power.

I expect it to be reasonably useless in urban areas, especially leaving home as I live by a fire stations, and you are never very far from an ambulance, policeman, pcso or fire engine. But it should still show rough distance and whether sources are getting closer or further away.

Edited by spookly on Friday 17th March 10:52

Why do you need it? - Are you not capable of driving in a manner that does not attract the attention of the Police?

[vonhosen]

frankenstein12 said:

vonhosen said:

frankenstein12 said:

Handing out speeding tickets will make no difference.

Of course it makes a difference, it will potentially change behaviour &/or ban from the roads those that don't change behaviour.

My behaviour choices are certainly influenced by the possibility of prosecution. If there was zero potential for it I'd be driving around a lot quicker than I do.

Wrong. Human psych 101.

If a police officer gives someone a ticket for speeding and even a lecture about their speed, when the person drives off the focus of their attention will be on the penalty and its implications. They will in the vast majority of cases feel very aggrieved for receiving a ticket and resentful.

This means that rather than focusing on absorbing any information given by the officer and changing their driving attitude the only lesson learned is that police are there to rip off innocent motorists.

Speed cameras are even worse. There is not even a chance of learning or adapting.

If there was a serious desire to make roads safer speed enforcement would be dropped to the least enforced driving offence. Most of the motorways in my local region are very high speed, free flowing and driving behaviour such as lane discipline is generally better than pretty much any other county I drive through.

It is very unusual to have accidents that either close or restrict traffic flow.

Counter that to for example Essex police. One of the worst police forces in the country jmo. I regularly had to drive up the a12 from London towards Ipswich. I regularly got caught in long traffic jams. Most often near a specific bridge over the A12 where they regularly parked a scam van just after a sweeping bend.

On one occasion there was a rear ender accident caused by someone panic breaking for the speed cam as I went past in the opposite direction on another occasion passing the same way the road was closed with police ambulance and fire crews and two very badly damaged cars one of which had clearly been hit from behind and spun into the central reservation nose first.

Interestingly there was a layby with a caf and one day heading home I pulled in for some lunch and the cam van was in its usual spot. While I sat outside eating my lunch watching traffic go by there were a number of very near misses from people panic braking.

The camera was blatantly causing lots of accidents yet they kept putting it on the bridge.

No, you learn that if you get don't change the behaviour there is a chance you get caught & if you keep getting caught you'll lose your licence.
If you value your licence you change, of course if you don't you'll continue.
I value my licence, so the threat of sanction influences my choices.

Whether I think I'm getting ripped off or not doesn't change that, whether I'm resentful or not doesn't either. Whatever an officer says to me doesn't alter it either.
I can't afford to be banned, it's too inconvenient, keeping my licence is far more important than doing 80 instead of 70 on a motorway, so I'll ditch the stress & save some fuel rather than play a daft game of roulette

Please don' try to tell me it doesn't influence my choices because I know it is influencing my choices (I know me, you don't).
That doesn't mean I've never exceeded a limit, but my choices are made with full knowledge of what I'm risking & an acknowledgement that I'm responsible for those choices in full knowledge of the potential outcomes. I pick & choose, just another exercise in risk management.

[vonhosen]

frankenstein12 said:

Greendubber said:

Are drivers totally void of any responsibility then?

Of course they are responsible. As a rule of thumb its likely that in the scenario of rear enders caused by mobile or fixed speed cam late brakers the person who runs into the back of them is clearly either not maintaining a decent following distance or just not paying attention. It is also fair to blame the idiot panic braking to a ticket.

It does not however change the fact that the speed cameras cause accidents rather than reduce them as they do not teach people to drive safely. All they do is teach people to resent police and to continue to drive like utter pillocks.

Easiest answer is for them to hide the cameras & use more unmarked cars instead.
The uneasier I am about knowing where they are, the wider the influence on my choices.

[frankenstein12]

vonhosen said:

frankenstein12 said:

vonhosen said:

frankenstein12 said:

Handing out speeding tickets will make no difference.

Of course it makes a difference, it will potentially change behaviour &/or ban from the roads those that don't change behaviour.

My behaviour choices are certainly influenced by the possibility of prosecution. If there was zero potential for it I'd be driving around a lot quicker than I do.

Wrong. Human psych 101.

If a police officer gives someone a ticket for speeding and even a lecture about their speed, when the person drives off the focus of their attention will be on the penalty and its implications. They will in the vast majority of cases feel very aggrieved for receiving a ticket and resentful.

This means that rather than focusing on absorbing any information given by the officer and changing their driving attitude the only lesson learned is that police are there to rip off innocent motorists.

Speed cameras are even worse. There is not even a chance of learning or adapting.

If there was a serious desire to make roads safer speed enforcement would be dropped to the least enforced driving offence. Most of the motorways in my local region are very high speed, free flowing and driving behaviour such as lane discipline is generally better than pretty much any other county I drive through.

It is very unusual to have accidents that either close or restrict traffic flow.

Counter that to for example Essex police. One of the worst police forces in the country jmo. I regularly had to drive up the a12 from London towards Ipswich. I regularly got caught in long traffic jams. Most often near a specific bridge over the A12 where they regularly parked a scam van just after a sweeping bend.

On one occasion there was a rear ender accident caused by someone panic breaking for the speed cam as I went past in the opposite direction on another occasion passing the same way the road was closed with police ambulance and fire crews and two very badly damaged cars one of which had clearly been hit from behind and spun into the central reservation nose first.

Interestingly there was a layby with a caf and one day heading home I pulled in for some lunch and the cam van was in its usual spot. While I sat outside eating my lunch watching traffic go by there were a number of very near misses from people panic braking.

The camera was blatantly causing lots of accidents yet they kept putting it on the bridge.

No, you learn that if you get don't change the behaviour there is a chance you get caught & if you keep getting caught you'll lose your licence.
If you value your licence you change, of course if you don't you'll continue.
I value my licence, so the threat of sanction influences my choices.

Whether I think I'm getting ripped off or not doesn't change that, whether I'm resentful or not doesn't either. Whatever an officer says to me doesn't alter it either.
I can't afford to be banned, it's too inconvenient, keeping my licence is far more important than doing 80 instead of 70 on a motorway, so I'll ditch the stress & save some fuel rather than play a daft game of roulette

Please don' try to tell me it doesn't influence my choices because I know it is influencing my choices (I know me, you don't).
That doesn't mean I've never exceeded a limit, but my choices are made with full knowledge of what I'm risking & an acknowledgement that I'm responsible for those choices in full knowledge of the potential outcomes. I pick & choose, just another exercise in risk management.

Von getting a ticket will influence your thought process but unfortunately in your case you are a member of the brainwashed. The simple reality is the vast majority of people on the roads who are not police zombies will learn nothing and see zero reason for driving change if caught speeding until they are at real risk of license loss due to accruing sufficient points and even then the system is so broken most wont lose their license at 12 points anyway.

Once someone has been caught numerours times they simply get ingrained and they learn nothing from it. Sadly this is where it seems all police and road safety groups fall down and fail entirely. They cannot be bothered to understand how peoples minds work and see how to work creatively to correct poor driving behaviour and attitudes.

The point of police should be to educate motorists and where necessary enforce the rules.

Similar to the differences between US policing and UK policing. In the UK the police are taught to de escalate a situation and try resolve it calmly and peacefully. In the US little emphasis seems to be placed on de escalation and it means situations that could easily end peacefully wind up with someone dying and a full blown investigation.

[vonhosen]

frankenstein12 said:

The point of police should be to educate motorists and where necessary enforce the rules.

I'm not brainwashed. I don't see speed as dangerous per se, but that's irrelevant to the threat it poses to my licence.
I'm quite happy that I could drive to what I consider an acceptably safe standard at speeds often far in excess of our speed limits. I also accept that would require me to travel at times far below the prevailing limit.

The Police are not educators, they are not trained to be educators & they shouldn't be educators.
The two roles don't go together.

If the people who choose not to alter their behaviour get points or get banned I've little/no sympathy for them. They get enough chances.

[turbobloke]

vonhosen said:

The Police are not educators, they are not trained to be educators & they shouldn't be educators.
The two roles don't go together.

Does that mean that BiB don't hand out patronising roadside lectures by way of education? Or are they moonlighting at the time?

Fortunately I've never had the pleasure but there have been one or two prime examples from You Tube vids posted over the years.

[PoleDriver]

For the first time since I've joined PH I find myself in agreement with Vonhosen's posts!
I have to say, who are you and what have you done with the real Von?

[vonhosen]

turbobloke said:

vonhosen said:

The Police are not educators, they are not trained to be educators & they shouldn't be educators.
The two roles don't go together.

Does that mean that BiB don't hand out patronising roadside lectures by way of education? Or are they moonlighting at the time?

Fortunately I've never had the pleasure but there have been one or two prime examples from You Tube vids posted over the years.

A verbal warning is an enforcement disposal. It's a warning not an educational class.

[anonymous-user]

vonhosen said:

A verbal warning is an enforcement disposal. It's a warning not an educational class.

It's more a personal indulgence to be honest. Perhaps if they acted more human they might better convey the safety message. But it's not about safety.

[vonhosen]

yonex said:

vonhosen said:

A verbal warning is an enforcement disposal. It's a warning not an educational class.

It's more a personal indulgence to be honest. Perhaps if they acted more human they might better convey the safety message. But it's not about safety.

No, their exceeding the limit may not have been a safety issue, or it may have.
The offence isn't defined by the speed performed being a safety issue.

[frankenstein12]

vonhosen said:

frankenstein12 said:

vonhosen said:

frankenstein12 said:

Handing out speeding tickets will make no difference.

Of course it makes a difference, it will potentially change behaviour &/or ban from the roads those that don't change behaviour.

My behaviour choices are certainly influenced by the possibility of prosecution. If there was zero potential for it I'd be driving around a lot quicker than I do.

Wrong. Human psych 101.

If a police officer gives someone a ticket for speeding and even a lecture about their speed, when the person drives off the focus of their attention will be on the penalty and its implications. They will in the vast majority of cases feel very aggrieved for receiving a ticket and resentful.

This means that rather than focusing on absorbing any information given by the officer and changing their driving attitude the only lesson learned is that police are there to rip off innocent motorists.

Speed cameras are even worse. There is not even a chance of learning or adapting.

If there was a serious desire to make roads safer speed enforcement would be dropped to the least enforced driving offence. Most of the motorways in my local region are very high speed, free flowing and driving behaviour such as lane discipline is generally better than pretty much any other county I drive through.

It is very unusual to have accidents that either close or restrict traffic flow.

Counter that to for example Essex police. One of the worst police forces in the country jmo. I regularly had to drive up the a12 from London towards Ipswich. I regularly got caught in long traffic jams. Most often near a specific bridge over the A12 where they regularly parked a scam van just after a sweeping bend.

On one occasion there was a rear ender accident caused by someone panic breaking for the speed cam as I went past in the opposite direction on another occasion passing the same way the road was closed with police ambulance and fire crews and two very badly damaged cars one of which had clearly been hit from behind and spun into the central reservation nose first.

Interestingly there was a layby with a caf and one day heading home I pulled in for some lunch and the cam van was in its usual spot. While I sat outside eating my lunch watching traffic go by there were a number of very near misses from people panic braking.

The camera was blatantly causing lots of accidents yet they kept putting it on the bridge.

No, you learn that if you get don't change the behaviour there is a chance you get caught & if you keep getting caught you'll lose your licence.
If you value your licence you change, of course if you don't you'll continue.
I value my licence, so the threat of sanction influences my choices.

Whether I think I'm getting ripped off or not doesn't change that, whether I'm resentful or not doesn't either. Whatever an officer says to me doesn't alter it either.
I can't afford to be banned, it's too inconvenient, keeping my licence is far more important than doing 80 instead of 70 on a motorway, so I'll ditch the stress & save some fuel rather than play a daft game of roulette

Please don' try to tell me it doesn't influence my choices because I know it is influencing my choices (I know me, you don't).
That doesn't mean I've never exceeded a limit, but my choices are made with full knowledge of what I'm risking & an acknowledgement that I'm responsible for those choices in full knowledge of the potential outcomes. I pick & choose, just another exercise in risk management.

Von getting a ticket will influence your thought process but unfortunately in your case you are a member of the brainwashed. The simple reality is the vast majority of people on the roads who are not police zombies will learn nothing and see zero reason for driving change if caught speeding until they are at real risk of license loss due to accruing sufficient points and even then the system is so broken most wont lose their license at 12 points anyway.

Once someone has been caught numerours times they simply get ingrained and they learn nothing from it. Sadly this is where it seems all police and road safety groups fall down and fail entirely. They cannot be bothered to understand how peoples minds work and see how to work creatively to correct poor driving behaviour and attitudes.

The point of police should be to educate motorists and where necessary enforce the rules.

Similar to the differences between US policing and UK policing. In the UK the police are taught to de escalate a situation and try resolve it calmly and peacefully. In the US little emphasis seems to be placed on de escalation and it means situations that could easily end peacefully wind up with someone dying and a full blown investigation.

[Guybrush]

vonhosen said:

frankenstein12 said:

Greendubber said:

Are drivers totally void of any responsibility then?

Of course they are responsible. As a rule of thumb its likely that in the scenario of rear enders caused by mobile or fixed speed cam late brakers the person who runs into the back of them is clearly either not maintaining a decent following distance or just not paying attention. It is also fair to blame the idiot panic braking to a ticket.

It does not however change the fact that the speed cameras cause accidents rather than reduce them as they do not teach people to drive safely. All they do is teach people to resent police and to continue to drive like utter pillocks.

Easiest answer is for them to hide the cameras & use more unmarked cars instead.
The uneasier I am about knowing where they are, the wider the influence on my choices.

Don't judge others by your standards. Hidden cameras make the resentment greater and drivers even more of a nervous brake dabbing nuisance.

[spookly]

4rephill said:

spookly said:

I'm currently building a tetra/airwave detector. Similar to the Python or Target BlueEye.

Built using a Raspberry Pi 3, an SDR and a small LCD screen. Just need to write a python or C++ gui for it and it'll work. I can already scan the relevant frequencies and identify the uplink radio chatter, but until I create an interface I can only see it on a waterfall graph or in raw csv data files.

It isn't breaking the law as the device is incapable of decrypting the traffic, and in this instance is not even capturing encrypted data samples, it simply scans the relevant frequencies several times over 4 seconds then reports back the strongest signal found.

After calibration it should be able to tell you roughly how far the nearest active (ie. switched on) tetra mobile unit is.
I'll set it to display a dB output, but depending on results of calibration I might also create:

• a graph output
• an indicator of whether receive strength is currently rising/falling (ie. likely moving away or towards source)
• number of active channels identified (identify higher/lower number of different sources)
• approximate distance (probably fairly coarse... something like <200m, <500m, <1mile) - this will be indicative only due to lots of factors (reflection, original signal strength, etc)

I already had the RPi 3, and the screen. So total cost is about £25 for a decent shielded SDR. If you wanted to buy all the stuff required on the cheap then you'd be looking at about £60-£70.

I then plan to add a Bluetooth media player, GPS speedo, and possibly add two remote HD cameras to make a dashcam. Will also put it into a case and maybe add battery/ups power.

I expect it to be reasonably useless in urban areas, especially leaving home as I live by a fire stations, and you are never very far from an ambulance, policeman, pcso or fire engine. But it should still show rough distance and whether sources are getting closer or further away.

Edited by spookly on Friday 17th March 10:52

Why do you need it? - Are you not capable of driving in a manner that does not attract the attention of the Police?

More just building it because I can. I already have most of it, and planned on buying an SDR anyway, so cost is next to nothing.

I seem to drive fairly fast compared to most but still have a clean license.... so I'd say no, I don't have a problem avoiding getting

[Greendubber]

spookly said:

Greendubber said:

So it'll still detect the hand held and vehicle airwave terminals in hato, fire and ambo vehicles?

Yep.
But better to be aware something is there, than not be aware at all.

Seems like an overly complicated solution to a very simple issue to me.

[vonhosen]

Guybrush said:

vonhosen said:

frankenstein12 said:

Greendubber said:

Are drivers totally void of any responsibility then?

Of course they are responsible. As a rule of thumb its likely that in the scenario of rear enders caused by mobile or fixed speed cam late brakers the person who runs into the back of them is clearly either not maintaining a decent following distance or just not paying attention. It is also fair to blame the idiot panic braking to a ticket.

It does not however change the fact that the speed cameras cause accidents rather than reduce them as they do not teach people to drive safely. All they do is teach people to resent police and to continue to drive like utter pillocks.

Easiest answer is for them to hide the cameras & use more unmarked cars instead.
The uneasier I am about knowing where they are, the wider the influence on my choices.

Don't judge others by your standards. Hidden cameras make the resentment greater and drivers even more of a nervous brake dabbing nuisance.

As I said earlier, resentment is neither here nor there. You change or you potentially lose your licence. That doesn't alter a bit if you resent it or not.
What's to dab for when it's not at all visible?
People dabbing in front don't worry me either, with the gap I tend to leave in front they could anchor up to a stand still & it's not going to be a big problem let alone dab.

[anonymous-user]

vonhosen said:

No, their exceeding the limit may not have been a safety issue, or it may have.
The offence isn't defined by the speed performed being a safety issue.

Wrong. Pretty much every time I have been stopped I have had the standard 'chat'. It's the means to justify the ends. It's a little different in the US, the police over here could learn a bit about how to give someone a ticket and not patronise them. But like you say it matters not what the general public think, I mean what possible benefit could there be from not alienating the driving community?

[Countdown]

Why do some people seem to get stopped so often?