Why GPS Data May Be Missing

Use this when

You open a recording in HumVision and the map tab shows no track, or you try to export a GPS track and get the message "There is no GPS track to export."

Common reasons

No GPS receiver was connected to the unit

Humminbird units record sonar without a GPS source. If your unit was running in standalone sonar mode — no chartplotter network, no external GPS puck — the recording will have no position data at all.

The unit had no satellite lock when recording started

If you powered on and started recording before the unit acquired a fix, the early pings carry a position of exactly 0°N, 0°E (off the coast of Africa in the Gulf of Guinea). HumVision filters those coordinates out. If lock was lost and never recovered for the whole session, the track will be empty.

GPS lock was lost mid-recording

Some or all pings may lack valid coordinates. The map will show only the portion of the track where lock was held. A short trip with interrupted lock can look like a broken or very short line.

The recording was made indoors or in a covered slip

GNSS signals do not penetrate metal roofs or concrete. Even a brief obstructed period produces gaps.

The unit was set to a mode that does not embed GPS in the sonar log

Some Humminbird configurations record sonar without writing GPS into the .son files. If you have ruled out a unit-side GPS configuration issue, this may be the cause. The only way to confirm is to check whether the unit's chart view was showing a position fix at the time.

How to check

1. Open the recording in HumVision.
2. Look at the Map tab. If it shows a blank map with no line, there are no valid GPS coordinates in any ping.
3. Try exporting via Export > Export GPS Track (GPX). If you see the toast "There is no GPS track to export," the recording has no usable coordinates.
4. Check the original recording files. Each .son file stores GPS in every ping header. HumVision reads GPS from the channel with the best data, filtering out pings where both latitude and longitude read as zero.

What to do next

• If GPS was never connected, the recording cannot be geolocated after the fact. You can still review all sonar channels, mark contacts, and export depth or intensity data.
• If lock was lost briefly, the track will show the portion that was valid. That may still be enough for your workflow.
• If you believe GPS was active and the track is still missing, check whether the same recording shows a track on the unit itself. If the unit shows a track but HumVision does not, please contact support and include the recording folder.