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Reed/Hall wireless sensor and receiver for .NET Gadgeteer


#1

Most modern security systems use a wireless reed or hall effect sensor to send entry detection information to a receiver. It would be great to have these and a receiver that plugs into .NET Gadgeteer.


#2

Reed sensors are simple switches. You can wire them to the extender module today. Is this enough for what you need?

Welcome to the community.


#3

He wants to connect a receiver and probably also decode the messages that the remote contacts are sending.

PS. You can make those remote contacts yourself for about 10€ including RF


#4

Wireless security devices most always have a bit of intelligence as well. Each device will have its own unique address and each device will send out a heartbeat signal periodically.


#5

Gus - on the sensor side I was hoping not to use a main board for each sensor as that would be expensive. Think of a home security system, the controller contains the main board and receiver and the sensors are simply stuck on to doors with a corresponding magnet. In this case the sensor is a combined Reed/Hall and wirelesss transmitter with some minor smarts.

Eric - Yes, the receiver is the module I’m expecting to interface with the main board. I think it would be reasonably straight forward to make the sensor using a main board and modules but my suggestion was to componetize it and sell it separately.


#6

This is exactly what I am thinking. All sensors connect through thin wires to one box, which is the security system, in our case it is the mainboard.


#7

In this case I want wireless sensors, which are more common these days. See the attached image of such a sensor in my house.


#8

I personally never seen those. The system I have at home and the one we have at GHI is all wired.


#9

kglynn,

so what are you exactly looking for?

a) to build wireless sensors and receive that data on a Fez board
b) receive data from commercial wireless sensors?


#10

b).

I see the sensors as a bulk commodity item. I cant find a source for such sensors hence my suggestion for GHI to make them along with a receiver. I expect the receiver to plug into a Fez board.


#11

Do you know the protocol that the wireless sensors use to transmit their data?


#12

No, I don’t even know of a sensor source so I really don’t know if there is a standard protocol.


#13

then why don’t you build those sensors yourself? You will spend at max 10€ for each sensor (excluding plastic case)


#14

Excuse my lack of knowledge; to create the sensor on my own it would seem I would need a main board, extension module, reed/hall effect sensor and a wireless module of some sort which is obviously pricey.

What are you thinking of?


#15

kglynn,

have a look here: http://wiki.vdbnet.net/doku.php?id=wsn

The only item missing in your case is a hall-effect sensor, but that would be another 0.1€ and a piece of PCB


#16

@ kglynn - you’ll find this very much a DIY community. Personally, once I figured out how much manufacturers of stuff like your remote sensor were (over)charging, I joined the club. I would recommend you do the same. It is much more rewarding. There is a long list of suggested gadgeteer modules on the Wiki. Feel free to add this one if you like.


#17

Eric, using a nRF24L01 looks really interesting. Unfortunately I need a bit more tutuorial than just a parts list as described in http://wiki.vdbnet.net/doku.php?id=wsn to make it happen as I’m a newbie on the hardware side of things.


#18

Have a look here: http://maniacbug.wordpress.com/2011/11/02/getting-started-rf24/