Gps speed questions

Ok I have several questions for y'all.
I have a Humminbird 788 and 798. The 788 has really erratic speeds when slow trolling. Example: .1 jump to .9 back to .2. Not really usable while the 798 works pretty good, might jump around .1-.2 but you can get a good average.
- Is there anything I can do to improve the accuracy on my 788?
- Can I link to my 798 and use that speed?
- Would a software update help?
- I can buy a helix 5 with gps for $285, would that be my best bet?


Sent from my iPad using Tapatalk

Make sure the unit has the latest software version ...

https://www.humminbird.com/faqDetail.aspx?id=3648

An external GPS antenna may also help some ...

Rickie



Rickie

Maybe an unfixed problem with the 788 as mine does the same... not reliable at slow speeds and not steady on gps coords when still. 998 with external ant is steady as a rock, even the speed reading on my Terrova with internal antenna is good.

Could I interlink to the 798 and display it’s speed on my 788?

If the 798 and 788 are both the HD models, they can be Ethernet connected and share GPS antennas ...

If either unit is not the HD model, they can only share waypoints thru the older Interlink system ...

Rickie

Well the 788 is hd but the 798 is not, so I guess that idea is out. I’ve done the update but haven’t had a chance to try it yet.
What about the helix 5?
How’s the speed accuracy on them?

I owned both of the units. I was never much pleased with the GPS on them. I up graded to a 899. I also have the high speed GPS puck on my bow unit (A HELIX 9). You didn't say if you are using the internal GPS antenna or not. I have both bow and console units on external. Other than that they are a very good unit, as far as the Helix 5 they are a good series of units. As I have had my 9 now for a year and want to up grade to a 10 on my console. I think you are battling slow update/refresh rates.

Both units are internal gps. But it looks like it’s nearly $200 for a puck and I can buy a helix 5 for $300.

The Book for my Bird says the GPS is Plus or minus 10 feet That is enough of an Error tolerance Is enough to make jumps in speed apparent at slow speeds.