No Sonar Channels Appear

Use this when

The recording loads without an error but the viewer is blank or shows no channel tabs, or only some expected channels appear.

Common reasons

• All .SON files are empty or zero-byte — HumVision detects channels by finding .SON files (B000.SON through B004.SON) and reading their ping data. A file that exists but contains no valid pings is treated as absent.
• Channel classification failed — HumVision identifies each channel by reading a median frequency value from the ping headers. If the pings report an unrecognised frequency (e.g. all zeros), the channel may appear as "Unknown" or not at all.
• Side Imaging channels not paired — SI port and starboard channels are detected by matching adjacent files with equal ping counts. If only one of the pair was recorded, neither shows as a side-scan channel.
• Recording from an unsupported unit — Very old Humminbird firmware versions use a different file structure that may not parse correctly.

How to check

1. Open Finder and confirm the recording folder contains at least one non-zero .SON file.
2. Check how many channel tabs appear in the top bar. If tabs appear but are labelled "Unknown", the frequency header in the file may be zero. The recording is still viewable, just unclassified.
3. For Side Imaging recordings, confirm the folder contains two adjacent channel files of identical size (e.g. B002.SON and B003.SON both at the same byte count). A mismatch means one channel was truncated.

What to try next

1. Open a different recording from the same session. If channels appear there, the original recording is likely corrupted.
2. If you expect a Down Imaging or 2D channel and only see side-scan tabs, check the Top Bar: all detected channels are listed. Switch to any available tab to view that channel.
3. Try a fresh recording: record 30 seconds of water, transfer the card, and open that file. If channels appear on a fresh file but not on your original, the original recording has a file-level problem.

If it still does not work

Contact support at support@gethumvision.com with the recording folder name and the number of .SON files present. Screenshots of the empty viewer also help diagnose the issue.