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aurgathor
join:2002-12-01
Lynnwood, WA

aurgathor

Member

detecting a police car

What would be some effective ways to detect nearby police car(s) when their radar is turned off, and when they are not visible for one reason or another?

Possible scenarios would be detecting one that's hiding behind a curve, or one following one or two cars behind during night time.

I'm thinking about the combination of various electronic signatures, but I'm not sure if they use unique frequencies, or what exactly is in their cars.

PS: No, I didn't get a ticket recently.

Bada Bing
WVU Mountaineers
Premium Member
join:2001-05-29
Fort Gay, WV

Bada Bing

Premium Member

I had the UNIDEN BEARCAT BEAR TRACKER scanner back in the 1990's and it worked great for State Police and others that had the mobile radio repeater in the trunk of the police cars.
The one I had:
»cgi.ebay.com/Uniden-Bear ··· ViewItem

This would be great side by side with a radar detector.
»cgi.ebay.com/UNIDEN-BEAR ··· ViewItem

Splitpair
Premium Member
join:2000-07-29
Cow Towne

Splitpair to aurgathor

Premium Member

to aurgathor
said by aurgathor:

What would be some effective ways to detect nearby police car(s) when their radar is turned off, and when they are not visible for one reason or another?
Over the years I have found that placing one foot on the brake pedal and another on the accelerator followed by a controlled release of the brakes just after hitting stall speed while in close proximity to doughnut shops works quite well. Note this works much better if played on the midnight to 8 shift guys.

Wayne

aurgathor
join:2002-12-01
Lynnwood, WA

aurgathor

Member

While attention from attractive members of the opposite sex is certainly desirable , I'm not exactly sure the same is true for the members of law enforcement.

cypherstream
MVM
join:2004-12-02
Reading, PA
·PenTeleData
ARRIS SB8200

cypherstream to aurgathor

MVM

to aurgathor
What about those who don't even use radar? They use stuff like Robic stopwatches.

I think you just have to look out for painted white lines on the roads, keep a look out on the sides of the roads and be cautious when driving around curves or blind spots.

Keeping an eye out for cops is like keeping an eye out for deer sometimes. Both have very bad consequences, but the deer can really hurt you if it flies into your windshield.

Blackbird
Built for Speed
Premium Member
join:2005-01-14
Fort Wayne, IN

Blackbird to aurgathor

Premium Member

to aurgathor
said by aurgathor:

What would be some effective ways to detect nearby police car(s) when their radar is turned off, and when they are not visible for one reason or another? ... I'm thinking about the combination of various electronic signatures, but I'm not sure if they use unique frequencies, or what exactly is in their cars. ...
Even if their cars contained police-only unique radio gear besides any radar, if that equipment wasn't itself transmitting, there'd be few useful emissions to detect and process. Unless, of course, you dug way down into the noise to correlate out their receiver local-oscillator/synthesizer leakage, etc... and unless you could also DF and range-capture on such signals in a meaningful way to allow your processing system to decide if the source was nearby or just some random capture from miles away.

The technology to do all that actually does exist, but it's generally used in other arenas. You can't afford it. And you probably can't obtain it legally. And if you did have it, you'd probably need a trained EWO to operate it while you drove merrily on down the road.

Wouldn't it be just a tad easier to make sure to drive under the speed limits...?

EliteData
EliteData
Premium Member
join:2003-07-06
Philippines

EliteData

Premium Member

said by Blackbird:

said by aurgathor:

What would be some effective ways to detect nearby police car(s) when their radar is turned off, and when they are not visible for one reason or another? ... I'm thinking about the combination of various electronic signatures, but I'm not sure if they use unique frequencies, or what exactly is in their cars. ...
Even if their cars contained police-only unique radio gear besides any radar, if that equipment wasn't itself transmitting, there'd be few useful emissions to detect and process. Unless, of course, you dug way down into the noise to correlate out their receiver local-oscillator/synthesizer leakage, etc... and unless you could also DF and range-capture on such signals in a meaningful way to allow your processing system to decide if the source was nearby or just some random capture from miles away.

The technology to do all that actually does exist, but it's generally used in other arenas. You can't afford it. And you probably can't obtain it legally. And if you did have it, you'd probably need a trained EWO to operate it while you drove merrily on down the road.

Wouldn't it be just a tad easier to make sure to drive under the speed limits...?
its interesting you say that.
many years ago, i did exactly just that.
in my county during that time, police vehicles were equipped with VHF transcievers.
i discovered what the local oscillator frequecny output was from these radios (the frequency changed depending on the transciever channel).
i setup a highly sensitive scanner with a short range omni cut for a certain radius of those frequencies.
while this method did indeed work, i found the distance not too pleasing, 50 feet to the police vehicle and i started to pickup a signal, by then, its a bit too late.
now my county uses a trunked 800Mhz system with GPS and a data terminal.
the next step i have is to go to a vehicle (officer is a friend of mine) with my hand held freq counter and see what solid freq pops up continuously (data term, GPS).
but lately, i havent really found a need to do this as my instincts and eye seem to be much better.

Blackbird
Built for Speed
Premium Member
join:2005-01-14
Fort Wayne, IN

Blackbird

Premium Member

The biggest problem is the real-world inconsistency of emitter signal strength. Since the "full-time" signals at issue are generally leaked unintentionally from usually metal-enclosed environs (partial or full), their strength will easily vary by over a greater than 30:1 amplitude range for all sorts of reasons. This makes it nearly impossible to reliably gauge range-to-emitter from signal strength alone, since just a 16:1 strength variation corresponds to a 4:1 inherent range uncertainty.

That pretty much forces one instead into a high-accuracy, direction-finding concept: one triangulates location of the emitter as one's monitoring platform moves along an understood path. But that, in turn, mandates on-board GPS plus very-high-sensitivity reception in order to pick up the emitter at distance sufficient to sample enough data for long enough to accurately triangulate emitter location in time to respond meaningfully. It's a tough problem, even for military systems at mega-buck levels. Inexpensive solutions either are full of false-alarms or weak and unpredictable in detecting legitimate targets.

W7PSK
Just Me
Premium Member
join:2000-12-04
Everett, WA

W7PSK

Premium Member

I used to Operate stuff like that back in the day. But it took a dedicated operator with a big rack of Top Secret Multi Mega Buck stuff to do it.

Like they say the best defense to speeding tickets is obey the speed laws.

whizkid3
MVM
join:2002-02-21
Queens, NY

whizkid3 to aurgathor

MVM

to aurgathor
Use a helicopter.