Humminbird 998 C SI depth problems

[bigminner]

Tried out my new 998c si today and am having problems with the depth readout and the water column in DI and 2D sonar. The depth reading will read right for a few seconds and then jump all over the place. The DI and 2D sonar are reading right for a few seconds and then the water column will go to 0. The SI seems to be working O.K., just the DI and 2D. The depth readout and water coumn jumping around don't happen at the same time if this makes any sense. My transducer is mounted on the jackplate and this happens at anywhere from 2 to 6 mph.
If anyone has any ideas that might help I would really appreciate it. If not I will call Humminbird in the morning.
Thanks,

bigminner

[Joby @ Humminbird]

My question is if you are sitting still does it read ok then. If so it may be turbulence.

[bigminner]

I did'nt think to check it sitting still, "DUH". If it is turbulence would it not affect SI also?
The transducer is appx. 2" below and 3" back from a step on the transom, and there is another step below that. It looks like it would be hard to find a place on the transom to mount it. I really can't mount if any further back on the jack plate.
I am going to go back out today and check it again.
Thanks,

bigminner

[rnvinc]

Check the software version currently installed in your unit....

I think versions 4.750 and earlier had shallow water depth reading problem..

This was supposedly fixed in 4.950 (someone correct my numbers if I'm incorrect)

Rickie

[Humminbird_Greg]

Let us know what your menu settings are if they are not on the factory default setting.
Also make sure that you did not have a second (or third or fourth…) sonar unit on as this could be sonar-to-sonar interference causing this.

[bigminner]

"Problem solved", I must have had a whole flock of senior moments yesterday as I never thought of the obvious. I have an older Stratos with an in-dash "flasher" that has a through the hull transducer. I am using it for high speed running. It was causing interference, which was messing up the depth readout as well as the DI and 2D sonar.
Everything seems to be working O.K. now, I just need to learn how to fine tune it and use it.
Thanks for the replys,

bigminner

[Humminbird_Greg]

bigminner,
Try running your indash flasher again but set the Noise Filter menu on your 998c Si unit to a higher setting to see if you can get them to ‘play nice’ together. This does not always work but it may this time...

[bigminner]

Will try, thanks

[Crappiegirl1]

greg,
my 2nd day in the water with my new 898c si. i have depth readings all over the place, no mater what the depth. i also see no fish symbols although its on and the fish are there. i am not happy that i can not find a dedicated screen to di or a dedicated screen to si. just combos whats with that? or have i missed something?

[Kenny]

Crappiegirl, check your view selection menu and see if your single screen views have been selected as hidden.