Trolling Motor Noise On My HDS 7??

[t_dub]

hey Nelly, I'm guessing you're gonna take this one so i'll just direct it at you....I get a lot of interference on my sonar from Honda 8hp kicker. I am ending up having to turn on the noise reduction to medium and knock the sensitivity down quite a bit (in the 70's) to clear most of it, but i'm afraid those two things are combing to wipe out most of my fish marks. if i don't, the screen can sometimes get blanked out like the sensitivity is turned up to 99. of course the time i get most noise is when it hits the rpm range needed for trolling. throttle down to idle and most of it disappears. also, when i troll on my main motor there is no noise.

is there anything i can do?

i've heard something about a certain kind of spark plug reducing noise. also, if this makes any difference, the kicker is mounted on the opposite side from the transducer, the HDS is direct-wired to the battery and the trolling motor is wired into my battery switch.

thanks

[Nelly]

Hey Dub,
Kicker interferance can be a major pain but if you've manipulated the noise reduction and sensitivity, you've definitely on the right track!

The spark plug issue is also a great point! NGK makes an "ES" series of plugs which stands for "Electronic Supression".

Spark plugs in this series have their part numbers preceeded by ES. in other words, if your engine takes a DR5-HS, then look for a ES DR5-HS.

Transducer cable routing has a great influence on interferance. Check to see if your 'ducer cable comes close to your kicker wiring. If so, Wrap your 'ducer cable in tin foil where it comes close to the kicker wiring.

If your kicker is an electric start model then you're stuck with having it join your electrical system but if it's a Honda that has the "charging wire" joining your elecrical system, try disconnecting the positive side.

As a last resort, try adding a separate, new grounding wire from a battery ground directly to your kicker. There is a chance that the static might just ground out and dissapear!

Good luck and let me know if that works for you!

[t_dub]

thanks for the tips Nelly. I'm going to look or those spark plugs today. it is an electric start so i've got the + lead wired into the battery switch and the - lead attached to a common - post that most of my other - leads on the boat (but not the HDS) go to, then a jumper to the batteries from there. not sure what you mean by adding another a new grounding lead from a battery to the kicker. where would I attach it on the kicker?

[Robbo]

Lots of good intel from Nelly as usual. Just an FYI from my experience...my optimal sensitivity setting is at around 74% on the HDS10 with the noise reduction set to medium the same as yours. My unit marks everything loud and clear

Prior to installing the Structure Scan I used to run at around 93% sensitivity, but now it seems like 74% +/- is the magic number. I had the Lowrance guys on the boat back in June and they were happy with the settings. When there are a lot of other boats around I sometimes have to drop the sensitivity down a few points to keep the picture clear. Hope that helps

[t_dub]

thanks Rob. had no idea what others ran their sensitivity at or their noise reduction, so that makes me feel better. and yeah, i'm surprised how much other boats sonar affects the noise level on mine. last week at sekiu, it was a mess in the mornings surrounded by other boats. my wife thought i was neurotic adjusting that thing all the time.

[Robbo]

Here's a photo that shows my settings T-Dub. Check out the king buried in the middle of this cloud of bait. Talk about a fat kid in a candy store

sounder_forums.jpg (92.12 KiB) Viewed 11727 times

[t_dub]

cool shot of that guy buried in there.

[Dan Carney]

Robbo, (Nelly, or anyone else...)
I see you were running at 200kHz. Do you run at 455kHz on your structure scan? I would be really interested in seeing screenshots showing fish at 455 if you have the opportunity to post some. I am running the Elite5 DSI and love the 800 kHz in shallow water, but am still getting used to running 455 in the sound. The more I use it the better I like it.
As far as t_dub's issue with interference from other boats, I was wondering if using a freq other than 200kHz (seems to be most common) would decrease interference and improve performance in those crowded trolling areas. Last Sat I was at Tide Point trolling among 60+ boats on 455kHz and had no interference issues. One last thought, when I installed my new unit it came with a filter that was wired inline between the fuse and the unit, do the HDS units use these filters an if not could one be added?
L8R
Dan

[Robbo]

Robbo, (Nelly, or anyone else...)
I see you were running at 200kHz. Do you run at 455kHz on your structure scan? I would be really interested in seeing screenshots showing fish at 455 if you have the opportunity to post some. I am running the Elite5 DSI and love the 800 kHz in shallow water, but am still getting used to running 455 in the sound. The more I use it the better I like it.
As far as t_dub's issue with interference from other boats, I was wondering if using a freq other than 200kHz (seems to be most common) would decrease interference and improve performance in those crowded trolling areas. Last Sat I was at Tide Point trolling among 60+ boats on 455kHz and had no interference issues. One last thought, when I installed my new unit it came with a filter that was wired inline between the fuse and the unit, do the HDS units use these filters an if not could one be added?
L8R
Dan

I run at 200 kHz almost all of the time except when we're fishing in really deep water. I'll switch over to 50 kHz in 180 to 400 feet of water. Most of the time I can tell if it's "business time" down deep on the 200 setting even though the marks aren't that clear. Matter of experience there I guess.

On the Structure Scan unit I'll usually run the 800 setting in shallow water, say less than 80 feet give or take, and the 455 setting below that. Suspended fish will usually appear as streaks on the screen and the bait is pretty obvious. I always split the screen and use the Structure Scan to find concentrations of bait and the sonar to locate fish.

A little fried right now and can't recall if my HDS units have those inline filters Dan. Nelly might know the answer to that one quicker than I can get back to you.

Hopefully I answered your questions and sorry for the delay in getting back to you Dan. I'll do my best to post some more photos.

[Dan Carney]

Robbo,
Thanks for the info and hope you have a great year up there.
I look forward to seeing more pictures when you have time.
L8R
Dan