'Thieves at the moment are using the latest technology, which can track a sat nav system even when it isn't on display in a vehicle'
news.bbc.co.uk/1/hi/uk/6325173.stm
Are they really, or is this poor reporting and the start of an urban myth ?
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Go on, get out of the car...
www.mikes-walks.co.uk
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Sounds like use of the Mark 1 Eyeball, spotting the suction pad or its mark, and breaking in on the off chance that it´s in the glovebox.
Urban myth.
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SFAIK a sat nav system is a receiver not a transmitter and if it isn't powered up I don't think it could be detected. However, years ago my ingenious father lost a radio controlled model a/c. He went home and built some sort of detector and found the a/c by the presence of its receiver before the batteries went flat so maybe there is something in the story.
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Both the reporter and police officer are talking out of the wrong orifice.
{edited to clarify who martin123 is referring to - DD}
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Most RF receivers give off some RF when powered up, but I doubt that 15 y/o wearers of hooded garments are using TV detector van technology to spot cars which may contain a badly-hidden satnav. More likely they spot the ring on the screen left by the suction-pad, or the pad itself still in place.
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The only way is if a: it has bluetoothand b: its switched on.
other than that its guesswork.
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TourVanMan TM < Ex RF >
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Probably picking up the local oscillator (455Khz).
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Some people (inc journalists) seem to have a belief that sat nav receiver units can be 'tracked' by satellite.
Almost all GPS receivers do not give off any form of signal that could lead to their detection. Some PDA-based systems may use Bluetooth to connect to a BT GPS receiver. But when the system is switched off the BT signal obviously disappears.
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The BBC report is completely true
bluetooth technology on a mobile phone, will search for other blue tooth devices, inc satnavs that are bluetooth enabled. I presume (but don't know) that the satnav would need to be turned on. Many people leave the satnav turned on if they are stopping for a short stop e.g. shop visit/garage etc, so that it doesn't take ages for the satnav to 'find itself' again. So the satnav locked in the glovebox will be detectable to the oik with a bluetooth mobile phone.
Thieves are looking for the sucker marks on the windscreen or the holder fitted to a dash board and then break into the car presuming it will be in the glove box, centre arm rest, under the seat or in the boot.....because that's where a significant number of people leave them.
police have set up 'sting' operations with tracking devices in satnavs, but this is an expensive option as the car gets the window smashed and the devices have still been stolen, never to be seen again.
the comment re ambulances is anew one to me, but doesn't surprise me as i'm aware of min-cabs being called and when they turn up, the oik hops in, grabs the sat nav and then runs for it.
Of course it wouldn't be a problem if people stopped buying 'bargains' in pubs or more recently e-bay. Surely everyone selling something like a satnav would have the box, the charger and the instruction book.....if not, why not.
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Many Bluetooth devices have an option to make the device 'detectable' - in other words, to allow it to respond to 'Are you there, Moriarty' messages from other devices. If this option is turned off, it allows you to limit your Bluetooth devices to a closed system - say just the GPS receiver and the display unit - and to prevent it from announcing itself to scrotes (that word again) with their own devices.
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Probably picking up the local oscillator (455Khz).
1/ A scroat would know nothing about local oscillators.
2/ Its ERP is so low that you would need a tuned discriminator to pick it up, and then at about 5 yards,
3/ it needs to be turned on.
all highly unlikely.
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TourVanMan TM < Ex RF >
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>> Probably picking up the local oscillator (455Khz). 1/ A scroat would know nothing about local oscillators. 2/ Its ERP is so low that you would need a tuned discriminator to pick it up, and then at about 5 yards, 3/ it needs to be turned on. all highly unlikely.
My reply was in response to picking up the 'lost' radio-controlled model aeroplane by detecting the LO in the receiver (which would work quite well) - but unforuntaly the post ended up in the wrong place in the thread.
A GPS receiver does not have a 455Khz local oscillator!
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All recievers have a LO of some frequency or other.
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TourVanMan TM < Ex RF >
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All recievers have a LO of some frequency or other
Yes, but not at 455kHz - my post was referring to the r/c model aeroplace receiver which would likely be working at 27 or (modern equipment) 35MHz. GPS carriers are in L-band (1.2-1.5 GHz) and so the LO is going to be operating in the MHz frequency range.
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Agree on the bluetooth issue. Same issue with bluetooth enabled laptops.
People will have to learn to not only hide their PDA/SATNAV/Laptop, but also turn the power off.
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Or make their device undiscoverable.
Recently I used a gizmo for a retail client. It sends out a message to any discoverable mobile with a message (in this case a 2 for 1 offer). The proportion of mobiles that were discoverable was 10%
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