Thread: CHIRP - Shallow Water

Test side to side with down scan. <*)}}}><

This isn't a DownScan review CC. Lowrance does not have CHIRP DS / SS.

GOOD JOB

Interesting study... thanks for posting that! I am looking at the Lowrance Gen 3... I do not have one yet so I do not fully understand your comparison. (applying different CHIRP frequencies etc.).. I fish in depths up to 60 feet so your analysis would apply to my situation. It seems the TM150 is at a "sweet spot" in terms of cost and performance. I really like how the Algae below the thermocline disappears when using the TM150. Is that because the sensitivity needed is less due to the better transducer? I would now be temped to pick up an HDS 7 or 9 without any transducers and purchase the TM150 and a LSS2 (side scan) separately. Would that be your recommendation based upon your tests?

Curious, what size are the targets?

I'm shocked to see how the targets are barely visible on the downscan side vs the sonar.

I guess everyone's definition of shallow/deep water is different, for me deep is 25' and shallow is 5' or less. I see no benefit from chirp technology for the way I fish, however it may be a good tool to catch fishermen.

John,
If I did this test above the thermocline, the sensitivity would have to be reduced dramatically which would take away from the target strength and some may use that as an argument, so I thought it best to do the test just below the thermocline.
My conclusion is that the Gen3 with the TM150 is a really great sonar match, not for CHIRP strangely enough, but for the higher fixed frequencies such as 105kHz.
The only benefit I see for CHIRP in shallow water, is when you are fishing from a stationary position above a brush pile for example, you will be able to track the fish better as they move through the cover.
Other than that, it's a deep water (>500ft) tool, especially with the high end CHIRP transducers such as the B175.
Hope that clears things up a little.
John Easton
Fisherman's Guide to Sonar
HighTec Fishing with John Easton