Quote Originally Posted by wicklundrh View Post
Having extensive knowledge in regards to grid and waypoint accuracy due to my time and training in the Marine Corps, I completely understand the technologies involved. I do however beleive that people have been sold a line of crap in relation to the point 1 antenna.

Placing the puck directly over your transducer isn't going to gain you a whole lot. The reason... most of these units operate on an 8 or 10 digit grid coordinate. An 8 digit grid is only accurate to within 10 meters. A 10 digit grid is only accurate to within 1 meter. 1 Meter you say... that is pretty close. Nope, not in relation to 1 meter of where you are at, but relation to within 1 meter of the "scale" of the mapping software you utilize.

" An often-confusing point is that most NIMA 1:50,000 scale maps are made to an accuracy of 50m
at the 90% confidence interval. This means that 90% of all well-defined points on a map will fall within a 50
meter radius of their actual position on the earth’s surface. The confusion comes in when soldiers try to
use a map to get a 10-digit grid coordinate, which equates to a 1 meter precision. A 1:50,000 scale map is
only accurate to 50m 90% of the time so a 6 digit (100m precision) or an 8 digit (10m precision) are more
appropriate. A 1:250,000 scale map maintains an accuracy of 250 meters at the 90% confidence interval."

So, having the puck over your transducer on an 18 foot boat where your helm is say, 6 feet away and your helm unit (with internal GPS) is sitting, is not any more accurate than simply utilizing the internal GPS software.

Relation has everything to do with mapping software and not the antenna. As for the heading, I've never had an issue with maps bouncing, spinning, or anything else. I troll 95% of the time. Whether it be on contours, point to point, or waypoint to waypoint.

That being said, if they give you the unit for free, you never sniff a gift fish, but I personally wouldn't purchase it as an add on. Not when you are talking mapping software that cannot realistically get you accurate enough to get you down within a specific perameter.