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Ladyada RF Question?
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Ladyada RF Question?

by Rico Bravo on Tue Sep 08, 2009 4:55 pm

Ladyada,
I am trying to build a wireless house alarm and I need transmitters that I can run off a battery. It seems like the xbee is over-kill and use too much power. Can you offer any suggestions?
thanks
Rico
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Re: Ladyada RF Question?

by zener on Tue Sep 08, 2009 5:22 pm

You didn't like the suggestions from a week ago?

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Re: Ladyada RF Question?

by Rico Bravo on Tue Sep 08, 2009 6:20 pm

Nope!!
Sorry.
But I did get a new suggestion, only transmitting when the door is open which would allow me to use the XBEE and save lots of battery power.
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Re: Ladyada RF Question?

by zener on Tue Sep 08, 2009 9:33 pm

Yes. Transmitting intermittently doesn't use much power, as long as you sleep the rest of the time. Receiving uses a lot more power, since you need to listen all the time, although there are ways around this, using their Digimesh system or similar synchronizing system.

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Re: Ladyada RF Question?

by Rico Bravo on Wed Sep 09, 2009 12:11 am

Sleeping,no, when the door is shut there is no power applied, so much better than sleeping!
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Re: Ladyada RF Question?

by richms on Thu Sep 10, 2009 2:50 am

I would say buy existing transmitters like the x-10 ones and then a generic 433 or 310 MHz reciver (whichever is used where you are)

The code for the insecure non rolling code ones is very well documented if you search online.

I doubt you can roll your own for less then the price of the ready made ones, by the time you allow for cases and battery holders etc once you include your time into it, and that you have something that has to look presentable when on the wall.

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Re: Ladyada RF Question?

by SiliconFarmer on Mon Sep 21, 2009 4:32 am

X10 Door/window wireless sensors can be bought in 3-packs for under $15 (ebay). $5 per unit would indeed be very hard to beat DIY - the economies of mass production.

Edward Cheung has what is probably the first writeup of the protocol on his web site at http://www.edcheung.com/automa/rf.txt. Google search will yield several other writeups, some of which include code. I'd guess that someone somewhere has written up an solution with source code for Arduino to receive wireless X10 data.

Arduino.cc itself has information on using a wired X10 receiver module with Arduino.
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Re: Ladyada RF Question?

by fat16lib on Mon Sep 21, 2009 9:04 am

A guy contacted me about a X10 logger he was building to log events to a SD card. He used a wireless X10 receiver to put the signal on the power line from the wireless sensor and then used the Arduino wired software.
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