I have been running my Micro-Mini for about two hours now and it refuses to get a fix. The LED remains off. The data output works perfectly and confirms there is no fix. I have moved the board outside, and no fix. The power is 3.3v
Can you Help me Richard
Is the antenna active? If so, is there an active circuit in place to provide voltage to the antenna? Sounds to me like it’s not getting enough signal to lock.
I am not getting a fix either.
I returned the Gps to Sparkfun for test
We took our GPS module on top of a 4 story empty parking lot and it could not get a fix after 2 minutes. Do these work still? Are the satellites not communicating with them anymore?
Has anyone recently gotten these to get a fix? Please respond.
I bought mine in late December (of 08) and mine gets a lock pretty well in my lab (College Station, TX). Although I think there is a problem with the Micro-Mini and TXing stuff to it…
can you please tell me how you got it working? I just put a 5v on the vcc and gnd on the gnd and the pps never goes on nor does what is on the TX ever say its got a lock…
Freak Nigh, have you tried tying pin 22 (marked 00, opposite PPS on the board) to ground?
It doesn’t say it’s nessicery, but it might work…
Here is the exact setup I am using on two of my products:
http://www.rpc-electronics.com/img/rtra … ematic.jpgA few key things:
Make sure Opt1 and Opt2 pins are GROUNDED to put the module in 4800 baud serial mode. This is TTL level.
RSV must be grounded, preferably through a 0 ohm resistor, but I actually just grounded it.
Make sure you are running the data through an ST202 or somthing sutible if going right to a serial port of a computer. You can also tie directly to a 5V uP without any inversion. In this application, I am just running it through a simple NPN transistor inverter.
Lastly, are you using any kind of active antenna? I found the active antenna was a big help with cold lock time and holding lock.
Hope that helps.
Well, you shouldn’t have to alter the hardware of Sparkfun’s products to get them working…
Thanks for the replies, I have tried grounding the OO but that didn’t seem to do it. I haven’t tried grounding the opt’s because they are harder to get to and it is already producing 4800 baud data stream. I actually dont have access to the RSV pin and the antenna comes with it. I have no clue maybe florida doesn’t have gps satellites over it.
Freak Nigh:
I have no clue maybe florida doesn’t have gps satellites over it.
I am NOT trying to be an ass here, but is that a serious question?
I just like to blame things on florida because im from the north.
Perhaps it’s the Bermuda Triangle. 
Leon
Lol, had a little ‘giggle’ there… 
I think the OPTion pads are grounded by default.
Jason, thanks for the tip about the ST202, I just sampled a couple of MAX202’s which are supposed to be functional replicas (mainly because i couldn’t find a ST202 to buy anywhere). Just so you know the Opt’s are actually already grounded.
So with all that in mind, trying to ground the OO… what else can I really do? I think all I can do is just send it back right and get another GPS module?
If your getting data back, and tried resetting it, all without a fix, i suggest you arrange a return. Save yourself from all the hassle.
I received a new one from sparkfun but the same problem, no fix, i think it is a bad antenna desing, i tested my other GPS (BU-353), same place, a fix in 30 sec.[/img]
Hello everyone.
We test all of our GPS boards for locks. The microMini GPS will get a lock in less than a minute outside here at Spark Fun. If you are having issues, the best idea would be for you to return the device back to us for testing. If you still are having issues, there could be environmental factors that are causing interference.
Things to keep in mind if you are having trouble; regulate your power supply (preferably to 3.3V in the microMini’s case), minimize interference from other electronics, try not to test the unit in you hand (the impedance will be raised and this will de-tune the antenna network), and be sure to test the unit outside.
