In the volumes you'd be purchasing you can get OEM GPS devices with a usb or RS232 interface for around $30-35.
Battery life is going to be simply dependent on the size of the battery I wouldn't bother with buttons, just have it start feeding when the power source is connected. Or implement a switch. There's no reason to have it on when it's not doing anything. Accuracy is a function of many things, but CEP <30m is quite achievable with even the cheapest OEM device under most circumstances. I doubt you're going to be able to build one with a transmitter for <$50 in small volumes though. It's not really sensible engaging in R&D for something like this unless you have specific requirements or are going to build large volumes. Too much hassle unless you're going to build hundreds or have unusual requirements (size, form factor, etc). You can get little zoombak trackers or garmin gps dog collars for around $80-100. There are many systems like this (just google gps tracking beacon or something), most involve a subscription around $10-15/month. That's probably your best bet. Here's an example - http://www.zoombak.com/products/universal/ - bri On Tue, Feb 1, 2011 at 7:24 AM, Paul Faunik <[email protected]> wrote: > > I'm looking to build a location transmitter that would have the following > constraints > > - low cost (sub $50) for the hw > - long battery life. based on the device broadcasting location every 5 min > and doing nothing else. days between charges? > - two simple buttons : start broadcasting : stop broadcasting > - the geo coordinates are relatively accurate most of the time - 30 meters > (used almost exclusively outdoors in San Francisco) > > One thought is it could some super cheap older model cell phone, some simple > native app to send geo coords to web service or send sms (if this > circumvents a data plan), super cheap pay as you go phone plan, put it all > in a box and just expose two buttons and the charging plug. > > Other alternatives? > > Anyone ever built or heard of such a project? > > thanks, > > Paul > > > _______________________________________________ > Geowanking mailing list > [email protected] > http://geowanking.org/mailman/listinfo/geowanking_geowanking.org > > -- Brian Russo / (808) 271 4166 _______________________________________________ Geowanking mailing list [email protected] http://geowanking.org/mailman/listinfo/geowanking_geowanking.org
