wireless module

Projects General Guidance
21

Paul_KD7HB:
Actual "holes" are not necessary. Google "slot antenna".

So a slot is not a hole ?

I will need to think about that for a while.

22

The slot could be nothing more than a slight gap at the corners of the enclosure.

Paul

23

Why does your project have to be in a metal box , and why cant you put an antenna outside the metal box?

24

Hello

Thank you everyone for your answers.
so finally we can conclude that if we keep device in metal enclosure it won't work.

I have a question regarding XBee pro which has antenna will it work in metal enclosure?
i want device to work for 15 meters range

25

bmg1234:
Hello

Thank you everyone for your answers.
so finally we can conclude that if we keep device in metal enclosure it won't work.

I have a question regarding XBee pro which has antenna will it work in metal enclosure?
i want device to work for 15 meters range

Rather tne waste the forums time, repeating the same question, why dont you just explain what the the project is, what the enclosure is, why it must be an enclosed box, all the stuff that is useful to us ..................

26

Hello

Project is alert system when truck fuel cap is open. this sender device will be placed on truck fuel cap if someone tries to open the buzzer will turn on. this system i cannot make using wire because someone can cut the wire and steal the fuel and also it will be in open space and it has to be protected by water.

Receiver will be in truck cabin so from fuel tank to receiver data should be sent using wireless module.

so our plan is to keep device is metal enclosure with out any holes.

Hope now you understood the project concept.

please let me know the solution.

27

bmg1234:
Hello

Project is alert system when truck fuel cap is open. this sender device will be placed on truck fuel cap if someone tries to open the buzzer will turn on. this system i cannot make using wire because someone can cut the wire and steal the fuel and also it will be in open space and it has to be protected by water.

Receiver will be in truck cabin so from fuel tank to receiver data should be sent using wireless module.

so our plan is to keep device is metal enclosure with out any holes.

Hope now you understood the project concept.

please let me know the solution.

Finally! Explain the fuel cap and how you are going to attach the enclosure to it and still allow someone to remove the cap? There are fuel caps and then there are fuel caps! Some are smooth, some have knobs for gripping, some are stainless steel, some are brass. Some are probably cast aluminum.

We need the whole picture. There may be other ways of detecting the cap removal.

Paul

28

People who dont understand basic stuff, electrics and fuel, not a good mix.

29

Paul_KD7HB:
The slot could be nothing more than a slight gap at the corners of the enclosure.

As long as its circumference or border length is one wavelength (or integer multiple), whether round or long. The situation is similar for the cross section of a waveguide. A slot has a particular radiation pattern.

30

bmg1234:
Hello

Project is alert system when truck fuel cap is open. this sender device will be placed on truck fuel cap if someone tries to open the buzzer will turn on. this system i cannot make using wire because someone can cut the wire and steal the fuel and also it will be in open space and it has to be protected by water.

Receiver will be in truck cabin so from fuel tank to receiver data should be sent using wireless module.

so our plan is to keep device is metal enclosure with out any holes.

Hope now you understood the project concept.

please let me know the solution.

Of course you can do this with a cable.

Fit a contact to the fuel cap that is closed when the cap is closed. Arrange it with a transistor or a small relay so that when the contact opens the buzzer sounds. That way if someone opens the cap or cuts the cable the buzzer will sound. You could add extra protection by having 4 wires in the cable instead of 2, and shorting the 2 spare wires out and arranging it so that if these 2 wires are cut then that also makes the buzzer go off. This is how wired burglar alarms work. Much less electronics that using a radio link. Anyway, in your proposed solution how were you going to get power to the transmitter without a cable?