Earlier this month I ordered an Arduino Nano from the eBay seller “beauty.2011″ and a Skylab SKM53 from “tommyvdp”, also on eBay. This week I received both packages in the mail, packaging was properly done and the items were new as described. If you are unsure from who to buy an Arduino or GPS module, I’d recommend those two. tommyvdp was also very nice, adding a sketch for reading the Skylab with an Arduino on the sales page. Here’s the original code on scribd, and here’s my own sketch currently, without the LCD parts and edited output.
Some example output:
Latitude : 59.330136 :: Longitude : 18.057404
Latitude : 59.330092 :: Longitude : 18.057339
Latitude : 59.330059 :: Longitude : 18.057275
Latitude : 59.329994 :: Longitude : 18.057146
According to the datasheet for the Skylab SKM53, it’s up to 3 meters accurate, and I found it to be sometimes a lot more accurate when you are in a large space like a field. Inside a standard house it can differ something like 10 to 20 meters. At my university though, it can’t even acquire the location and return 0.0000000, 0.0000000. No surprise to be honest, the building is pretty big with lots of network cables and systems. If I leave the building with the GPS turned on, it almost immediately locates itself, which is pretty neat.
But that’s not all, as it has to be a pretty compact system while leaving the Arduino reusable I bought a few strips of 1/10″ sockets for on a PCB. I can solder this to some protoboard and easily put it on without soldering it directly. This protoboard is also going to be the place where I hook up the Arduino to the GPS module and some powersupply I still have to think of. Not to forget logging all data to an SD card.
The SD part is also going to be interesting, as I would like to have everything stored as plain text, so I can easily read it via a normal computer but most simple libraries write to the card as if it was internal storage. Another module with library does store in plain text I believe, but the module is 20 euro and not so compact. So I’ll figure out how I’m going to do that.