Its here because I cant be bothered with my own install

Archive for May, 2011

Cheap RFID reader.

Bought this – was crazy cheap so why not

http://search.ebay.com/280649380492

RFID reader and 10 tokens for it.

Here are some internal pics of it.

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Weather station reciever breakthru – sortof.

Remember how I was basically copying what was done on the practical arduino project but with my cheap ebay temperature sensors?

Well, from reading and looking online I have found that they are made by Fine Offset.

But thats not the point. I saw that the new neighbours had a weather station (actually there are 2 they have – no idea why 2) – it looks like a fine offset one. So I know you know what I was thinking. I can get readings from that instead of buying my own one (which I have been planning on doing anyway)

So, because its so far away from both my server closet, and my workspace, and I hadnt seen any new sensors pop up I decided I would have to try recieveing closer to the property boundary.

I had built the 433MHz reciever onto my xbee shield as I didnt have a protoshield at the time. (the seeed one has a small proto area on it)

So I added the xbee and got that all setup for a wireless link – massive issues, till I dropped the baudrate from 115200 to 38400, but then it started working as ususal getting about 1 in 10 readings from the closeby sensors and 1 in 20-30 from the far away ones.

Off to sort out a battery for it. I had some 6 AA backs I got off ebay a while ago so I crimped a header on the end that would fit into the red JST I was using back when I had some LiPos that used that connector (they are gone now, started to puff up)

Anyway, as soon as I moved over to battery power, I started to get every sensor of mine, every single time without fail.

I did a range test down the driveway to the limit of the xbee range, and I was still seeing almost every single update from the sensors.

Clearly there is an issue when powered from the USB that is not there when powered by 7.2V and then regulated down to 5V. I will try adding capacitors to it once I have my soldering iron working again.

No sign of any data from any sensors other than the 6 of mine, so either there is a different RF protocol for the full weather station, they have a 868MHz model, or else they just dont have batteries in it.

Since I now know I can get reliable RF reception, that sortof motivates me to get around to making the code to take the data to pachube work properly.

I still have to get a weather station tho if I want to get wind and rainfall data. Mitre10 had some digitech ones that were fine offset I believe, so thats going back on the shopping list.

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