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To tell you the truth, the idea of making a GPS circuit wasn’t in my mind at all, until I have seen this video on Youtube 3 years ago.

Then I thought to myself why not make a GPS circuit as well, it seems easy and pretty cool! I will just buy this GPS module called Parallax GPS from Grand Studios and then I could start my very own GPS Navigation System!

I did buy this Parallax GPS module under this link: CLICK HERE. To tell you the truth 80 bucks for this GPS module is pretty expensive. I was so excited to make this module work, and show me my coordinates where I am testing this module from. But the result where pretty shocking and not good!

Why?
1- In this youtube video, they don’t show you the time that it takes such that it locks to the satellites. For me it took approximately 10 minutes to just lock to 3 satellites.
2- The error of this module is terrible, and I am not talking here about +/-10 meters, but I am talking about -/- 1 kilometer (might be slightly less or slightly greater), and gave me an altitude about 200 meters above sea level, which I far doubt, because I live near the coast!
3-For one reason, I don’t believe this video because at the end they made geocasching, and they pretended that they found there treasure by the GPS circuit that they made, which I really doubt.

Ofcourse, I was thinking of making several projects with this module, but the readings where extremely shocking. So, I went for the Telit Module GM862 QUAD GPS. You can buy the whole thing (Board + GSM/GPRS modem + GPS Antenna) for $113. Yes, it is more expensive than the Parallax module but you can’t get a GSM/GPRS modem for $33??

Ok, when you buy this module it comes with a GPS antenna called SIRF III, and this antenna locks with 6 satellites in less than 30 seconds (NOTE: both tests where done from the same place). The accuracy of this antenna was so good (only +/-1meter). Added to this you have a GSM/GPRS module so you can do lots of things with this kit.
CLICK HERE

So, a piece of advice if you have the money to buy a GPS module go for the Telit GM862 QUAD GPS and don’t buy the Parallax GPS module, and if can’t afford buying the Telit GM862 try to buy this board EasyGPS (CLICK HERE) and it costs about $90. I haven’t tried the EasyGPS board at all, but what I can assure you is Mikroelektronia sells excellent products.

To Bre Pettis (the person who made this YouTube video)
I really like your Hacks and the youtube videos that you make; but please if there is something bad in somebodys circuit try to mention it out (like the GPS of Joe Grands)

In the end, I will upload a Satellite picture from Google Earth that compares both modules, when it is tested in my car. But for now, I can show you a test that was done by UC Davis (but there is no Parallax GPS antenna here). Have a look yourself.

And if anybody have any questions please don’t hesitate to ask!