I am trying out Sonar Viewer under the 14 day trial period. I have a Lowrance HDS 7 Gen 2 sonar with structure scan and a Point-1 GPS/Compass connected via NMEA 2000 network. I recorded several sonar log files (sl2) with the Point-1 as the only GPS/heading source and noticed when I play sonar logs back in Sonar Viewer, there is no heading data shown. It only displays "---.--" for HDG. What am I missing?

Did you check the option "Use headings when available" in the file load screen? If you didn't, check this option and re-load the file (it won't change the loaded file).

It was selected when I loaded a sonar log file but still no heading showing when playing back the file.

If you want to share the file (Google Drive or equivalent - send link to This email address is being protected from spambots. You need JavaScript enabled to view it. ) then I can take a look. It sounds as if headings haven't been recorded.

I uploaded a sample sl2 file via Google Drive with link sent to support.

I had the same issue with my lowrance HDS7 Touch. I have a home made heading sensor connected via NMEA 0183
looks like upgrading to HDS_Gen2_Touch-5.0-53.1.108-Standard-1 fixed it for me.
before the upgrade using sonar viewer output to csv file i got T Heading valid but all the values were 0
after the upgrade, there is actual heading data!!!!

hopefully someone else can confirm for NMEA 2000 sensors

Channel Frequency HeadingValid Heading[rad]
Primary 83kHz T 0
Downscan 455kHz T 0
Sidescan 455kHz T 0
Primary 83kHz T 0
Downscan 455kHz T 0
Sidescan 455kHz T 0

after upgrade

Channel Frequency HeadingValid Heading[rad]
Primary 83kHz T 4.3792
Downscan 455kHz T 4.3792
Sidescan 455kHz T 0
Primary 83kHz T 4.3792
Downscan 455kHz T 4.3792
Sidescan 455kHz T 0

I just installed software version 5.0 on my HDS7 and took to the lake to record some files. As noted in the previous post, it now seems Lowrance has decided to fix the heading data issue because it is shown in my newly recorded files. Lets hope it stays that way.