TZ Touch with GP33 poor accuracy



I have a new 14" TZ and the boat's location fix has poor accuracy (off by approx a half mile). The unit receives its location signal from a GP33 and its supplied antenna.

When viewing the satellite signal strength on the Skyview screen, none of the satellite’s signal strengths are greater than 50%. The GP33 antenna has a clear view of the sky and relocating it has had no effect. The GP33 antenna is one month old and the cable has not been compromised. The antenna has never been exposed to radar.

I have attached two photos to illustrate. In the photo of the chart, the boat's actual position is between the two channel marker, but the screen shot is showing our location well outside the Charleston jetties


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  • chart.JPG
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You are over zoomed the chart. Your photo is cropped where you can't see it but in the range scale it will be RED when you over zoom beyond the scale of the chart. This is more of an issue with RASTER (like yours showing) because it is a scanned paper chart that the system can not re-scale. Try using a vector chart when you get in very close in and watch the if the range box turns red; it is telling you something.