After you all mark something (fish/brush) how do you stay on it? Even with the HB casting rings set at 30 feet, that's over 700 sq ft in area (if my math is right) to try to hit your spot..and stay on it. I'm struggling with SI. I do a little better when I mark something with the bank as a reference but out deep I don't feel I'm even hitting my spot. Any suggestions?

That can be tough.  I added an external GPS antenna with Heading Sensor.   Really helps.

 It includes an internal compass that always knows true North.  This allows for a more precise readout of boat position and direction and assists in maintaining that accuracy particularly when traveling at slow speeds (under 3 miles per hour).

http://www.humminbird.com/Products/AS-GPS-HS/

A-Jay

I also have trouble with this. Right now I use a marker buoy and i pick an object on the bank to align with. So when I line up with the buoy and the spot on shore it should be pretty close. Still not perfect but can't afford the 360 sonar so its my best option

28 minutes ago, A-Jay said:

That can be tough.  I added an external GPS antenna with Heading Sensor.   Really helps.

 It includes an internal compass that always knows true North.  This allows for a more precise readout of boat position and direction and assists in maintaining that accuracy particularly when traveling at slow speeds (under 3 miles per hour).

http://www.humminbird.com/Products/AS-GPS-HS/

A-Jay

Interesting, so it's more accurate than the internal one?

The threshold for the O position curser is .6 mph. The Heading Sensor eliminates that and always shows the direction the bow is pointed by rotating the map. Above .6 mph you get the Course Arrow=the direction the boat is going.

The point of the Casting Rings is to position your boat on the ring and cast to the center of it. You choose what the radius of that Ring is. I use 30'.

Took this screen shot while fishing a brush pile. You can see the brush pile on the 360 view and the boat's relation to the Casting Ring, waypoint, and direction the bow is pointed.

Since waypoints are displayed on the 360 view, most of the time I just have that displayed and see where the waypoint is, the brush pile is, and where them fish things are:

 

 

This area has a lot of trees laying on the bottom. The two waypoints are not within range of the 360 setting of 40' but the Chart shows them and where they are in relation to the boat. Just shows you can use the Heading Sensor and Casting Rings to hit your target.

While I always carry markers with me and believe that they are the best/easiest overall, in many situations I don't want to drive over a spot first, or get too near, or I might only be planning to make a few casts just to check a spot. In those cases, I have no problem using both casting rings and SI to position myself. I use a 40' ring, and it is usually a simple matter of knowing direction of approach to get the right lineup. In other words, I'll approach a spot head-on so that the initial casts are going to literally be straight ahead of me toward the target, making sure to slowly stop the boat at the rings edge. If for some reason winds won't allow a direct approach, I'll slowly idle by one side of the casting ring using SI, then drop a buoy when I see what I'm targeting. That way, I only need to keep my boat positioned on the buoy to make the correct cast. If you use some other method, the idea of dropping a buoy right over the front of the boat the first time your cast contacts your target still is a great aid for all future casts and positioning on the spot.

-T9

1 hour ago, Todd2 said:

Interesting, so it's more accurate than the internal one?

Yes.

A-Jay

Helix internal GPS antenna in my den:

Internal GPS for a Humminbird 798:

Heading Sensor connected to Humminbird 1198:

 

 

 

Thanks everyone, I think the external antenna with heading sensor is what I need to prevent that flickering of boat direction when I slow down to cast. Unfortunately my fun fund at the moment is allotted for other purposes....lol, vacation. Knowing why it's happening (going less than .6 mph) is very helpful. I'm going to try the buoy at the edge of the ring before slowing down.

The reason the position curser changes to a O is GPS cannot determine direction unless there are consecutive track points in a direction within a certain amount of time.

Other brands just have the position curser wander around on the chart view when going slow or stopped. Lowrance has a heading sensor GPS antenna also (Point 1).