(1) Update your software: GPSMAP Series with SD Card software version 2020.0902.1
as of September 2, 2020
This will allow for you to have the Depth Range on the screen like the forward range and gain are.
Note: recommend to always use an SD card. 32G or lower is best. It does not require an Ultra SD card or higher than 32. In fact, that will cause issues with your upload/download. Never do an update via ActiveCaptain/ Wi-Fi as that is sporadic in that it stops and starts. During the stopping and starting, you will miss key components in the update causing your unit to not receive a fully updated software. This is a big issue with software horror stories and causes your unit to act up.
(2) TVG stands for Time Varied Gain. It is a function used that reduces the amount of clutter in the fish finder display mode by varying the gain throughout the water column. Increasing the TVG increases the maximum depth that the TVG is applied to.
Note: when you turn it on Low, Med, or High it will remove clutter as well as your structure and jig.
(3) A good battery will do you justice. This equipment is power-hungry and sensitive to low voltage.
I run a dedicated Lithium 80 ah battery. Livescope is good up to 24v. The higher your voltage, the happier the system is.
Note: We marry the power cable for the GLS10 module and the Display unit together. Positive to positive, negative to negative. We then utilize a 10 gauge marine-grade wire and connect the positive to the positive and negative to negative of the GLS10 and Display unit and carry that on to the starting battery or dedicated battery. Never will we take a short-cut to a fuse panel or accessories switch. Early on it was not required but recommended to utilize a switch to kill the GLS10 module. Garmin with-in a software update some time ago allowed for the unit to become the switch to power off the GLS10 module through the network cable.
(4) I tell all of our customers to keep it simple. Only make adjustments to Gain, Forward Range, and Depth Range. "it is ok to adjust the color palette in sonar setup Appearance"
Note: Gain on average is best at 58-68. Deeper the water Higher the Gain. Shallower the water lower the Gain.
Here are several videos I recorded via Active Captain.
Note: Clarity and voltage in the video. Settings are factory defaults. Gain is 58-68
Crappie striking the jig 3 times
30' forward range, clear image at 12.5v
Large school of Catfish "blues"
30' forward range, clear image at 12.3v
Large school of crappie on a laydown
20' forward range, clear image at 12.5v
Large school of crappie on a creek ledge. A one man limit came from this one stop in 1-1/2 hour
20' forward range, not as clear of an image due to 11.4v