Humminbird Side Imaging Forums

Side Imaging Forums => 798c SI => Topic started by: nicknight on June 27, 2011, 01:18:30 PM

Title: 7ft lake....1000ft reading???
Post by: nicknight on June 27, 2011, 01:18:30 PM

I have been out twice with this unit and the 2nd time out the trouble started:

-reads ~400ft then 1000ft intermittently for long periods of time (minutes)
-SI charts stop moving.
-reseting the unit and recycling the power was not always the answer but usually was.
-this started happening and continued for a couple of hours then stopped
-a bowmount garmin 2D unit was likely on during this whole time and hooked up to the trolling motor
-trolling motor and main batter have different grounds
-trolling motor was on during these lockups but I recall it stopping at least once when it was not powered.
-the mapping functions were working
-it is a weedy lake but the transducer did not have weeds on it I think would interfere
-trolling speed about 1.5mph......I think it also locked while just drifting at .25 mph
-unit is hooked up to main battery (not the trolling motor battery).
-The base unit was rained on the day before but would have been long dry before the head unit was plugged in.


not sure what to do with this.......any suggestions on what might be wrong?

thanks,

nickNight

Title: Re: 7ft lake....1000ft reading???
Post by: ITGEEK on June 27, 2011, 01:54:39 PM

Suggestions for starters:
1) Make sure your unit is running the most up to date software.  Check Humminbird's Web site.
2) Load test your battery.  Just because it charges up doesn't mean it's any good.
3) Make sure all connections (electrical and transducer/accessory) are good and tight.
4) If your sonar is not hooked to it's own dedicated battery, then get one.  It doesn't have to be a big battery.
5) If your sonar wires run parallel closely to any other electrical wires, then cross them at right angles (like a cross).
6) Make sure when your boat is in the water at operating weight, that your transducer is adjusted so it's looking straight down.
7)Try bending the power cord connections outward a little to get a better connection.  WARNING:Bend one at a time or you will blow a fuse.  Don't ask me how I know this. ;)

Lastly, if  you've done all of the above and are still having problems, call Humminbird customer service at 1-800-633-1468.  Be polite and calmly explain the problem to them and ask them what they suggest you do next.  They'll get to the bottom of it.  9 out of 10 times, it's the battery, connections, or electrical interference.

Good Luck.

Title: Re: 7ft lake....1000ft reading???
Post by: Humminbird_Greg on June 27, 2011, 05:31:41 PM

nickNight,
Make sure that the Garmin (or any other sonar unit) is not on and causing sonar-to-sonar interference.
Make sure that the trolling motor, or any other electrical device, is not causing interference by making sure that they are turned off and than see if this happens again.
If the weeds are thick enough than they can impair the unit’s ability to get a correct water depth reading.  So see if this happens elsewhere on the lake/river that you were on that does not have weeds.
If possible; try testing your 798 unit on someone else’s boat that is using a Humminbird unit (any model will work for testing the 2D sonar).

Title: Re: 7ft lake....1000ft reading???
Post by: nicknight on June 27, 2011, 06:02:00 PM

OK, will do:

1)  I will make sure that the other fish finder is off.....I am thinking that it is the most likely culprit but wouldn't it cause more frequent interference for shorter periods of time than go and lock the unit up?

2) the trolling motor was on and off....it was off for sure (for at least a minute) at least once....so does that mean it is not causing it?


thanks

Title: Re: 7ft lake....1000ft reading???
Post by: Humminbird_Greg on June 29, 2011, 01:37:25 PM

If the 2D sonar is being interfered with and cannot track the bottom, the unit will slow or stop the chart updates for all sonar while it tries to figure out where the bottom of the lake/river really is.  Sonar-to-sonar interference can be constant or intermittent as can trolling motor interference.  I just want to make sure that either of these is or is not the culprit before going on to any other troubleshooting.

Title: Re: 7ft lake....1000ft reading???
Post by: nicknight on July 09, 2011, 05:29:27 PM

Have been out 3 times without using the other FF and have experienced no lock ups.  So it must have been the source.
I hope Humminbird fixes the error handling in their units so they don't crash when they get interfered with. 

Now if HB says the head units don't crash due to interference my unit is broken.  So I hope they fix the firmware soon.

nn

Title: Re: 7ft lake....1000ft reading???
Post by: Humminbird_Greg on July 12, 2011, 11:30:08 AM

nicknight,
There are only a limited number of things that we can do through software.  The only way to totally eliminate the possibility of sonar-to-sonar interference would be to change the transmit/receive frequency of one of the units.  That would probably mean a whole new unit would have to be designed and marketed and would cost more than the current units would due to the increase in cost of non-standard components such as a custom piezoelectric element for the transducer (this is the reason why the Si transducers cost so much now).

Title: Re: 7ft lake....1000ft reading???
Post by: nicknight on July 12, 2011, 03:00:16 PM

Electronics and programming background here.
It is a software issue I was on about.....the electronics interference can't be avoided.....it is how the software handles readings after the interference that is is/was perplexing me.  My other units showed interference and kept plugging along or maybe the CPU just can't keep up.   

Everything is doable but not everything can be done.....that is my motto so I am sticking with that on this one and maybe switching the other FF.

thanks,

nn