Poor GPS accuracy with MTSMC-H4-GP

[Shane Dunne]

I’m working with a MTSMC-H4-GP-P1-SP. With the GPS antenna connected and mounted outside where it can see 6 or 7 satellites, I’m getting GPS fixes but they’re off by 20 km.

Typical interaction transcript:

AT#GPSGETMESSAGE

#GPSGETMESSAGE:

$GPGGA,151528.005,4414.9883,N,07631.7387,W,1,07,1.2,88.9,M,-33.0,M,,0000*56

OK

I’m consistently getting 44.1498 deg N, 76.3173 deg W, but my location is 44.2497N, 76.5290 — some 20 km away.

Am I missing a setup/calibration step?

[Lonny Knudson]

Hi Shane,

The output in the $GPGGA sentence for the longitude and latitude fields is in degrees and minutes. I’m speculating you expressed your location in degrees.

44.2497 degrees expressed in degrees and minutes would be

44 degrees + (.2497 * 60) minutes = 44 degrees + 14.982 minutes.

For longitude:

76.5290 = 76 + (.5290 * 60) = 76 + 31.74

[Shane Dunne]

That’s it! Thanks Lonny!

[Author]

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