Thread: HDS GPS performace

I seem to have a difficult time getting right over the top of the brushpiles with the Lowrnace HDS GPS. Usually i just get close and then find them with the fishfinder up front with the TM. Would I be better off with an external GPS, would this give me satisfactory results? Or would I be better of with another source for gps such as a Garmin unit? Any Advice?

the downscan should give you a great picture of the brush i dont think the gps will have anything to do with it, its the transducer,sonar and or structure scan. if your not picking it up then you have it angled incorrectly or its not working correctly i would say, ---------------but i am no expert. a call to lowrance maybe

Sorry I didnt explain the problem very well. The picture is great on the unit , but when the chart shows that I am sitting right ontop of a marked brush pile "waypoint" there is nothing showing on the structure scan. Usually i have to move around a 15-20 ft circle to find it. So to me it seems like the GPS is inaccurate.

Do you have the refresh rate set to time? Here are the instructions I copied from BBC.


Press menu twice, hylight chart then press enter, arrow down to "waypoints, routes, trails" and press enter. Use right arrow and hylight trails, then press menu, arrow down and hylight settings and press enter. In box called logging type change that to time. Then in box below that which says time period change it to 1 sec then exit back out.

Originally Posted by Tenntomm

Sorry I didnt explain the problem very well. The picture is great on the unit , but when the chart shows that I am sitting right ontop of a marked brush pile "waypoint" there is nothing showing on the structure scan. Usually i have to move around a 15-20 ft circle to find it. So to me it seems like the GPS is inaccurate.

I know what you are saying. I can use my little hand held Garmin e-trex and get right back to the spot. When I use my HD, I maneuver the boat to my waypoint then have to look around a bit to find the exact spot. The e-trex has a has a "go to" feature. It has an arrow in a dial that point to the waypoint and tells you the distance to the spot. I feel like I can get back to the exact spot with the e-trex.
On the Low, I feel like I can only get close. I'll try what justin61 says but I think I'm missing something and wish someone would explain how to be more accurate with the HDS
GPS. Maybe I need to zoom in on the spot even more then move to it. It would make the margin of error smaller. There has to be a better way.

zooming in may be the difference, do a test, and mark a waypoint zoomed all the way in, and mark another spot when zoomed out some, maybe 50 or 100' and see if that makes a difference. I use a garmin HH gps, and have waypoints/structure marked/saved, and if you miss the spot by just a little bit, the HH will not beep. I can see the structure on the FF but I may be off the "mark" a bit.

I've been considering the external antenna that has a refresh rate of 5 times a second. (I believe this is correct.) Tom will chime in and inform us all about it.
I do know what you mean though. If I mark a waypoint by scrolling the cursor to the center of a brush pile I like, It gets me close to it. But, I take into consideration that the internal GPS Antenna (My HDS-8 Head unit) is a good 3.5' away from my LSS-1 Transducer and about 3' away from my 2d Transducer.
When I mark a waypoint, it's marking the spot of my Head unit, not the spot my Downscan is showing.

With the external Antenna, I can mount that over the top of either transducer within inches of it. Not only would I have a faster refresh rate as to where I actually am, I would be marking the spot more directly. Also, when I am trying to zero in on a waypoint, I always have the GPS zoomed in as far as it will go. It will not show the waypoints if I'm aways from them, but I will follow the trail lines that are left in the memory until the waypoint shows.

If anyone knows where I can find a bargain on a new 4000 antenna, lemme know.

I had the same problem. It helps to have the HDS head unit close to the transducer., especially in shallow water. I installed the LCG4000 external antenna and now I have no problem finding stuff. However, I still trust my Garmin more. I really got the LCG4000 for slow trolling accuracy and direction below .5mph. LCG4000 makes a difference for me. I actually went out with billbob the other day without my Garmin. No problem, but I wasn't overrun with confidence without the Garmin either.

Also, best to zoom in max. At present, my HDS7 will only zoom in 50 feet, but I only have base maps on it. Not happy with this crap zoom restriction at all.

I zoom in and I have zero problems, when it says i am on brush, i am on brush, hd7 or hd8 try zooming in as far as it goes, I hope it works for you

Thanks JustinP61. My refresh settings were wrong, so know it is refreshing at 1/sec but it's still not accurate. Let me try to explain the test i conducted. After i changed the refresh settings i saved a waypoint exactly where the boat is setting in my carport. I then started a goto for that waypoint and left the trail turned on while zoomed all the way in to the 50ft scale. Initially it said i was within 10ft of the waypoint, over a period of approxiamtely 3 min, it ranged from as close as 3ft to as far as 45ft from the waypoint. The boat HAS NOT MOVED. I dont understand why it is this inaccurate, The gps fix is showing 3D the whole time.....not exactly sure what that means . I have also made sure the WAAS enabled is turned on. There is no possible way to stay on top of a brushtop if it is doing the same thing on the water, and from my past experiece I would say that it is. I conducted the same test in the same location with my 2000 model magellan handheld and it never got further than 3ft from the target. Somebody please help. BY the way mine is the HDS8.