Long TTFF with SparkFun GPS Breakout - NEO-M9N

GPS/GNSS Development Boards
1

I’m trying to evaluate the TTFF for a SparkFun GPS Breakout - NEO-M9N compared to a standard and quite old U-Blox EVK-6H evaluation module. I use the same external antenna sitting in front of the same window in my office for both the EVK-6H and the Sparkfun GPS breakout.

I’ve run the following test on both boards

  1. Power up the receiver

  2. Send a cold start command from the U-Blox U-Center application to the Sparkfun and EVK-6H boards

  3. Make sure the receiver is configured to send nav messages

  4. Wait for the first fix.

Not surprisingly, the uBlox EVK-6H gets a fix in less than a minute. The Sparkfun board is still looking for a fix after 20 minutes. According to U-Center, it does see one or 2 satellites occasionally but not long enough to even sync time.

It seems like there is some setting that is set correctly on the EVK-6H that is not set correctly on the GPS breakout and is preventing getting the first fix in a reasonable time. Any idea what that setting might be?

2

There’s a battery on the board that’s probably dead when you receive the GPS, we recommend leaving the GPS powered for a few hours with the antenna attached to get that battery charged up. That will improve your TTFF and a cold start should get a fix fairly quickly after that.