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Mystery object for door opening

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Hi Everyone.

Looking for help identify an object that is used to open automatic doors.

To explain-

My Dad lives in a sheltered accommodation complex.Each resident is issued with a key fob that when put in front of a automatic door receiver opens the door.

Trouble is these are £20 a throw and we have to purchase a number of these in order to open the door when going to tend to our relatives.Each resident as the same trouble where some families spending £60 or so just so they can get in.

I purchased two of these fobs, 1 to get in and 1 to open up to see what worked it.

There is not much at all in the fob only what looks like a copper coil and a very tiny metallic object attached to the coil at two points.


Many of the residents misplace these fobs and subsequently have to purchase more as only one is issed free:mad:.There is no monitoring of these fobs by the council on issue as we can purchase as many as we like for our relatives.

I mentioned to some of the residents the fob might work in the form of a wrist watch and they expressed interest in this thought.

Can anyone help identify this object and if so what does it do?
please see image.

Regards Mark
 

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The image is showing now, hopefully someone will recognise it soon, although it doesn't look particularly clear.
 
The image is showing now, hopefully someone will recognise it soon, although it doesn't look particularly clear.

Thanks for that!!

Unfortunately the object is so Small it's very difficult to photograph so I scanned it instead.

The tiny rectangular metallic object in the item in question.It can't be much bigger than 1.5" square. The coil that comes out of it at two points goes around the internal circumference of the case.

There are no signs of any power source to this object

Mark
 
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hi mark ,
i wanna ask u a question, how does that object u sent open the door?
do u have to enter it in a speceific hole or is there any button in it??
 
It looks like a RFID device. Very specific coding inside, I doubt you can get something off the shelf.
 
If it is RFID,and it looks like it, and if you bought another, it won't work unless programmed into the system. This is how they keep the unwanted out.
 
If it is RFID,and it looks like it, and if you bought another, it won't work unless programmed into the system. This is how they keep the unwanted out.

Hi gerty & mike

MMMM!!! i'm thinking you maye right here. I googled for RFID and this is what I found-

http://www.technovelgy.com/ct/Technology-Article.asp?ArtNum=1


Does this men it is the end of the line for me in finding a cheaper or better solution? or can they be re-produced? it's a very small chip!!!

Mark
 
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In the link you provided, see Zombie tags. You would need a scanner (Not easy to get) and the tech know how to do this. I think your stuck :(
 
the way these tags work is the tag transmits an encrypted number to the reader which then sends it to a central controller which compares the number against authorizations. If OK, it then unlatches the door. You can probably find a reader fairly cheap but the hard part would be constructing a tag that transmits the right code. it's probably doable but you would first have to crack the encryption - I'm guessing it's AES.

maybe a better way to do this is find a source for the tags, they are usually a few dollars, er quid, and get the facillity people to use yours. I suspect they put such a high price on them to take into account the need to program the number into the system.
 
the way these tags work is the tag transmits an encrypted number to the reader which then sends it to a central controller which compares the number against authorizations. If OK, it then unlatches the door. You can probably find a reader fairly cheap but the hard part would be constructing a tag that transmits the right code. it's probably doable but you would first have to crack the encryption - I'm guessing it's AES.

maybe a better way to do this is find a source for the tags, they are usually a few dollars, er quid, and get the facillity people to use yours. I suspect they put such a high price on them to take into account the need to program the number into the system.

Unless you find some illegal outfit, no one is going to crack the code and produce counterfit devices. I believe there are laws against such things.
 
Hi,

I guess you are following the wrong trace. A metallic object for access control can't be an RFID chip. It has no conductive areas at all.

An I-Button has conductive areas, one for the data and one for ground. If the object you have to hold inside the receptacle isn't much larger than a PC RTC-battery (dimensions F3-type: 3.1mm, dia 17.35mm; F5-type: 5.89mm, dia 17.35mm) and also looks similar it must be an I-Button.

To use I-Button access systems without any control is pure waste of money.
Each I-Button has a unique number programmed into the chip during manufacturing. For controlled access the ID must be programmed into the control computer to accept a certain I-Button.

The type of the button should be engraved in the housing. Normally it is a DS1990A, manufactured by Dallas/Maxim semiconductors.

If there is no control at all you might purchase a couple of buttons at Mouser or Digitech for far less than you paid until now.

It wouldn't be wrong to post a picture of the "key" here too.

Boncuk
 
Unless you find some illegal outfit, no one is going to crack the code and produce counterfit devices. I believe there are laws against such things.

Hi Mike

Yes something I have considered and I would be very careful and keep within the Law.

This is the research stage of the project and it might not ever go anywhere.It all depends on where the fobs come from what they are and if there are any council/supplier contracts involved.It might even be that the local Council who own the complex don't have any input to the coding in the device.

I can do some research in to who supplies these fobs to the local council.

Mark
 
Hi,

I guess you are following the wrong trace. A metallic object for access control can't be an RFID chip. It has no conductive areas at all.

An I-Button has conductive areas, one for the data and one for ground. If the object you have to hold inside the receptacle isn't much larger than a PC RTC-battery (dimensions F3-type: 3.1mm, dia 17.35mm; F5-type: 5.89mm, dia 17.35mm) and also looks similar it must be an I-Button.

To use I-Button access systems without any control is pure waste of money.
Each I-Button has a unique number programmed into the chip during manufacturing. For controlled access the ID must be programmed into the control computer to accept a certain I-Button.

The type of the button should be engraved in the housing. Normally it is a DS1990A, manufactured by Dallas/Maxim semiconductors.

If there is no control at all you might purchase a couple of buttons at Mouser or Digitech for far less than you paid until now.

It wouldn't be wrong to post a picture of the "key" here too.

Boncuk



Cheers Boncuk for the info.

I have put in another clearer image of the item in question.

You say it could be an ibutton !! I can see your thoughts on this but on close inspection there are no markings on the surface of the device and I feel as you describe an Ibutton then this device does not match that description.

The device is approx 1.25mm square the device is glued in place so without removing it I can't be sure of it's thickness but I would guess at 1mm or so.

I googled on the DS1990A (ibutton) and it does not resemble this as I see it. none the less the Ibutton looks a great product.

I will still asume that it's an RFID chip until it's shown I'm barking up the wrong tree!!

Cheers Mark
 

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Hi all
After further research I am now also convinced that the device as sated a RFID chip.

I will require a scanner/writer to make further "passive tags" These can be purchased quite cheaply.

obviously there are legality issues in reproducing clones of the original fob and not knowing these Legalities I will leave well alone until I seek further info from the Local Council :eek:

Thanks for all your help.

Mark
 
Hi Mark,

I'm convinced that there are legality issues. If you could just insert any chip house security would be sacrificed.

If somebody looses his fob he will receive a registered one which is also contained in the comparison list of the access control computer.

Cloning such a device you might be faced with the charge of burglary (at least attempted burglary).

So it would be wise to get as much information as possible from the local council about those fobs and if possible, the system. (I doubt you'll receive any info about the system)

If the spare fobs are prepared at your local council there won't be any other way than paying the astronomic price for them - or take better care not losing them.

The I-Button system appears to me far cheaper than this RFID thing. There are special fob holders on the market just made to make the fob bigger to avoid losses.

You also might get familiar with the idea that local councils tend to purchase the most expensive and most useless stuff. (At least they do in Germany, so why not in other countries)

Hans
 
Hi Mark,

I'm convinced that there are legality issues. If you could just insert any chip house security would be sacrificed.

If somebody looses his fob he will receive a registered one which is also contained in the comparison list of the access control computer.

Cloning such a device you might be faced with the charge of burglary (at least attempted burglary).

So it would be wise to get as much information as possible from the local council about those fobs and if possible, the system. (I doubt you'll receive any info about the system)

If the spare fobs are prepared at your local council there won't be any other way than paying the astronomic price for them - or take better care not losing them.

The I-Button system appears to me far cheaper than this RFID thing. There are special fob holders on the market just made to make the fob bigger to avoid losses.

You also might get familiar with the idea that local councils tend to purchase the most expensive and most useless stuff. (At least they do in Germany, so why not in other countries)

Hans


Cheers Hans

I have yet to speak to the Center Warden about the issue and I am sure that the council have pre-purchased a quantity of already programmed tags what quantity I don't know.

What is quite concerning in the way of security is many of the fobs are purchased by the residents for none relatives such as none contractual cleaners , helpers and the odd job man.This leaves the center quite venerable.

I'm sure these fobs could be as little as £5 for me to produce but I'm now thinking this will also have a negative effect on security , the cheaper they are the more they hand out:eek:

I'm thinking more of chanaging some the fobs to suit the persons needs say a tag in a wrist watch or maybe a sticker tag on a Mobility Scooter just to make it a little easier for some of the residants.With this in mind I can approch the council.:D and see what they say:eek:

Not something I've thought too deeply about just yet as first off I had to find out what tech I was dealing with.

BTW. Yep the council around here in south yorkshire (UK). do seem to spend lots of cash on the wrong things and very little on the right things but that's another toppic and probs another forum!!!!

Thanks to all Mark
 
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