Help! My GPS says I'm in the ocean!

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Well-Known Member
Aug 14, 2014
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Okay, here goes.

My Missileworks RTx gives me coordinates:

My BRB gives me:
4125.6395 H165
^07159.0949 V206

When I punch either of those into my iPhone, the map drops a pin In the Atlantic Ocean near Block Island, RI. I can assure you that I'm not there. My phone estimates that position is ~160 miles from my current location.

How do I resolve this?
Longitude is usually specified either as West, or in a negative number. Try putting a negative value in for the value beginning with 7.

Also, the values shown don't have a delimiter after the degree value. You may also need to put a space after the first two digits.
Remember, latitude will always be between 0-90.
Longitude should always be between 0-180.

Unless you're not using degrees. There's also, rads, grads, state planes, and the military grid system. [emoji3]

Steve Shannon
Last edited:
Thanks guys. I had tried entering the coordinates with the negative sign before. Without it I am in Uzkebestan.

I tried the space idea with the negative sign and was successful.
How many satellites are you getting? Are you inside or outside?

Punch coordinates into Google Earth and see where it shows you?
If you're using default coordinate display on the RTx LCD, the coordinates are in decimal minutes (native to the uBlox7 UBX packet).
There's some conversion required if migrating coordinates across different formats.

Looks like these are "home" coordinates based on Google Earth (off Pumpkin Hill Road)?

Here's a coordinate example with the datum you posted and general Lat/Lon formats:
That's good to know, thanks Jim. I guess you have a program that can convert between the formats? I don't think I need to perform that step now that I have a reliable data configuration that can be processed by my phone's map function.
The Garmin GPS in my truck puts me about ten miles off when I am in the area of El Paso.
It goes back to being correct when I get out of the area.
You can select 1 of 4 display formats for your LCD, and the base will convert the display appropriately.
Choose the one that's going to be most compatible with your GPS app.