Reed/Hall wireless sensor and receiver for .NET Gadgeteer

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.

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.

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

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.

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.

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.

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

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


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?


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.

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

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

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

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?


have a look here:

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

@ 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.

Eric, using a nRF24L01 looks really interesting. Unfortunately I need a bit more tutuorial than just a parts list as described in to make it happen as I’m a newbie on the hardware side of things.

Have a look here: Getting Started with nRF24L01+ on Arduino | maniacbug