Humminbird Side Imaging Forums
Side Imaging Forums => 797c SI => Topic started by: whitefish on October 23, 2012, 08:27:00 PM
-
Hi Guys - I picked up a used 797 c2 this spring to replace the really old Raymarine on my Lund Tyee. Pretty happy with the unit but having a few problems that I'm hoping you can help me with.
I soon as I got the unit, I upgraded the unit firmware to the most recent version (5.450) with no problems doing the update. Given that I'm most familiar with traditional 2D sonar, I started working in this mode. This is where I ran into problems. Note that the unit is always run in 200/83Hz and in Freshwater Mode. All scenarios below have been on the Red River or Lake Winnipeg in Manitoba, so pretty silty water with lots of algae at times. Fishing depths are generally between 10 and 30 FOW (Feet of Water). I have the skimmer SI transducer that the unit came with mounted on the boat. I put the SI transducer in the same spot that the Raymarine transducer was mounted.
1) With Fish ID, I have yet to identify a fish while the boat is moving on plane. I do occasionally see arches but rarely. Not going all that fast - after all the boat will only top out at 35 mph.
2) The unit has identified fish when anchored in 10-15 FOW, but not consistently.
I contacted Humminbird and eventually I got a reply from a Tech that suggested turning up the sensitivity settings, moving the transducer, using Max Mode and separating the 797 unit wires away from the other wires in the boat. I moved the sonar and GPS wires (couldn't really move the power wire) with no change.
I also decided to get the head unit and transducer checked out at a certified Humminbird repair center. No problems were found.
Finally I decided trying to test the sensitivity of the unit (and how well I mounted the transducer) by jigging a 3/8 oz lead jig just below the transducer. I also had a 587 CI HD to try and compare to my 797. I did this test on Lake Winnipeg in 14 FOW with Water type set to Freshwater, SwitchFire set to Max, and 200/83 Hz:
- I first tested the 797 with factory sensitivity (200 and 83 Hz) settings. I could not see the jig at any depth. I started raising the sensitivity unit I could see the jig consistently. This was between 16 and 18 out of 20. Raising 83Hz sensitivity helped, but marginally.
- I then tested with the 587 using the my 797 mount. I was stunned. Without touching a single setting, I immediately saw my jig with a strong red return. The return was also much more fluid than that on my 797. When I moved the jig I saw an immediate motion on the 587, no delay. It was like I was painting the line with the rod! When jigging using the 797 there was a noticeable delay between my hand motion and what I saw on the screen.
Is any of this normal? Is this what I should expect from the 797?
Thanks
-
It sounds like your 797c2 unit has a transmit power problem that should have shown up when it was tested at the repair center. This could also be why the unit is not showing any fish ID symbols.
-
It sounds like your 797c2 unit has a transmit power problem that should have shown up when it was tested at the repair center. This could also be why the unit is not showing any fish ID symbols.
Thanks Greg - I'll inquire with the repair center and see what they say. Just to make sure its not the transducer, I'm going to test the 797 with the new 587 transducer to see if the 2D sonar works.
In you experience, does the 797 have a relatively slow chart speed and, for lack of a better word, "jerky" response on screen?
-
I'm also going to test the unit on a separate stand alone power supply. The unit is hooked up to a single 12v battery that is shared by all electrical on the boat including he main motor (3.0l mercruiser), stereo, lights etc. The unit is wired into the main fuse panel.
I have noticed that the 797 will shut off when I crank the motor, likely due to a power drop below 10v? While operating (motor off), it will usually show around 11.5v and up, but will drop to 11v on occasion.
I know the 797 has a higher power rating than the 587, so maybe this also explains why the 587 worked out of the box and the 797 didn't?
-
Good point whitefish. The 797c2 Si unit will have a higher power draw than the 587ci HD unit does. Test it on the separate battery and also with the other transducer. If you don’t see an improvement than the problem is in the unit.
If you battery has been registering that low than you either need to look into your wiring (loose or corroded) or a replacing your battery.
-
I was having similar problems with my 798 when I first got it. I ran new power and grounds wires directly to the battery. (Not through the fuse block) use wire no smaller than 14 gauge.since I rewired it I have not had any problems.. Also I would check your battery it should not be dropping below 10 volts when starting the motor. I have also found that using 200 kHz and max mode works best when trying to see your jig or drop shot.
-
Thanks Speedtroller. Snow is flying now, so I won't be able to test until next spring. I had hoped to get out one more time to try out, but not in the cards this year.
I can't recall exactly what the voltmeter was dropping to, but it was at around 10v.
I bought an ice ducer, so I'll see how it works out this winter ice fishing. I'll post back with my first results.
Fish
-
UPDATE - I bought a Humminbird Ice Ducer for ice fishing this winter and used it with both the 797 and 587. Hooked up to a small 12v AGM battery for power. WAY better results. I can still see the jig perfectly and no lag on the reaction on the screen (a problem I was having with the 797). Plus I can turn my sensitivity way down on the 797 (closer to default settings). So its definitely not the unit. Still not sure if its a transducer or power problem. This spring, I'll try the installed setup in the boat (compact sidescan ducer) using the portable battery instead of the main engine battery and see if this makes any difference. I can also put the iceducer overboard and compare results.