Topic: GPS difficulties on unit

[wolfs4evr]

Greg,

Why is the internal GPS on the 798 so horrible?  I don't pay too much attention to it since I use the console for navigating but it is a pain to find marked spots again since the accuracy of this unit is so sketchy.  Jumps all over the place even sitting in one spot.  The driveway.  100 foot swings all over the place yet the GPS screen says accuracy estimated 4 foot, etc.  I can set the 798 to the 898s puck and it doesn't do it at all so doubting it is software related.  When I was messing around a bit ago making sure everything is working correctly I marked a spot on one unit then marked a spot on the other to be sure they were going across the Ethernet, they were, and noticed that the spot I marked on the 798 was over a 100 feet off on the 898s screen.  I know the two antennas are +/- 17 feet apart so I would expect to see something closer to 20-30 foot difference from one unit to the other on marked spots not a huge number.

Acquiring a position is horrible too.  The 898 will acquire my position in seconds after booting up and the 798 takes upwards of 5-10 minutes to acquire a 3D fix.

Note from moderator: split this topic out of the other topic to keep it seperate..

[sjefsrafsern]

have you tried to offset your map? maybe it would get better if you did that?

[sjefsrafsern]

forget that, it actually sounds like there is something wrong with your unit. we have 2 older units with internal antennas and both of them are quite fast and wery accurate. but we have never linked them to other units.

[sonar2000]

I think these internal antenna units are very sensitive to location of install and that nothing obstructs the satelite signal to the unit..

Once Hb put external antennas out there it was not as bad..in fact with the grs50  it is quite good..

Just recheck your mounting location..

Chuck

[wolfs4evr]

The unit is on the bow of a 17' deep V.  There is nothing but sky anywhere near it.  lol

Don't pay attention to the audio...  I am not a good commentator.

I shot a couple vids on the cell phone.  The quality is horrible but the general idea is there.

This one is the 798 using internal GPS.  I am on a 50 foot scale.  It took 5 minutes for it to get a 3D fix.  I let it sit for about 5 minutes after that then dropped a point and cleared the track.  As you can see in it I am all over the place.  Upwards of 200 feet away from the waypoint several times.  The speed is jumping from .5 to into the 3mph range constantly moving.

http://youtu.be/UaCbncJ41BM

In the next video I left the unit on and powered up the console 898/puck mounted on the back of the boat.  I let it settle then changed the Ethernet settings on the 798 to use the 898/puck for GPS.  I am on a 10 foot scale and let it sit for 5+ minutes.  This looks correct.  I am hardly moving anywhere.  The point I dropped at most is only 15 feet away or so.  Acceptable.  Big difference.

http://youtu.be/YSEzu2bDJT8

[sonar2000]

Wolf....do you think this may another of the issues with ethernet connect as compared to standalone.
Or do you think a single unit issue..

Chuck

[sonar2000]

Received a reply that this issue for the 798 will be reposted to the 798 topic are as it appears to be a 798 issue...

Chuck

[wolfs4evr]

Single unit. Might just be a bad internal GPS antenna connection? Maybe it is software? Dunno other than my 798 jumps all over the place when using the internal GPS and is as smooth as it gets when I use the 898s GPS via Ethernet. When I recorded the 798 internal GPS video the console 898 was off. The speed is useless to look at if one is trolling since it jumps sooooo much. If up front I use the I-Pilot remote to tell how fast I am moving.

[Humminbird_Greg]

I would think that it is something amiss with the internal GPS Receiver wokfs4evr.  Contact Humminbird about getting this resolved.