Humminbird 345c Portable Ice Flasher noise / interference with marcum and other

[ggpr]

Hello everyone,

I have a humminbird 345c portable fish finder that i have purchased the ice transducer for and use it as a flasher.  Just recently my friend bought a marcum lx3 and when out fishing within 10 ft of each other we generate noise/interference between each other.  After fiddling with settings on both of our units he was able to basically get rid of my noise (i believe) and i was able to tone down the noise on my machine enough to still reference  what a fish was and roughly where my lure was when the situation presented itself.  The noise i was suffering was an occasional pulse of lots of lines on the flasher column at different depths and thicknesses and line density.  I dont recall seeing the interence lines moving so i was able to jig my lure and identify what it was by the expected movement on the flasher from a jigging lure.

His unit had multiple interference rejection levels to chose from and some worked half decent and he eventually found on that completely blocked me out..  At the same time i was tweaking settings on my unit to try and block him out so i cant say the exact IR level or setting on my unit that helped him...

Does anyone know if there is a interference rejection mode or setting for the humminbird 345c?  Or any settings that i could tweak to best remove the noise on my machine.  He is a really good friend of mine who i will most likely be fishing alongside for many hours in the future and i really would love to fix this... for the sake of our friendship... just kidding haha.

But seriously i would really love to know how i can fix this.  i managed to tone it down by playing with the sensitivity and noise filter settings, also setting the unit to the narrow cone 200 khz beam.  At the time i was fishing in 38 feet of water so i was able to set the sensitivity low and really make the sonar return bars thin which really helped with the noise not cluttering up my circuluar graph too much when it pulsed in.   Aside from settings on the machine (which i fear i may not have a simple IR mode selection like my buddy has on his) are there any other tricks i could possibly try to reduce noise between machines?  Hanging my transducer lower that his in the water column???  I would really like to know how we can fix this so i dont end up going out any buying a compatible unit or something haha.

Any help would be appreciated.

[3300]

not knowing your fish finder, i can give a few tips.
one is too keep your gains to a minimum. second is to keep your beams set to narrow and try to sit away a little further so the others return ping isn't trying to bounce back into your ducer. setting yours to narrow tries to not read the over lapping ping returns.

if you have no IR, then look into buying one that has one and keep the current one for the boat or to use alone on ice or return it or sell it.

whats the manual say about its IR?

did you contact customer service about it yet?

[matzilla]

from the sonar menu to go noise filter > adjust from there

make sure switchfire is in clear mode, manually adjust the max depth

[ggpr]

not knowing your fish finder, i can give a few tips.
one is too keep your gains to a minimum. second is to keep your beams set to narrow and try to sit away a little further so the others return ping isn't trying to bounce back into your ducer. setting yours to narrow tries to not read the over lapping ping returns.

if you have no IR, then look into buying one that has one and keep the current one for the boat or to use alone on ice or return it or sell it.

whats the manual say about its IR?

did you contact customer service about it yet?

Thanks for the tips,

By beam do you mean the sonar feedback bars that indicate a fish or bottom etc.  I generally try to make it as small as possible to see my lure.

I did check the manual and just brief mentions of IR but no actual setting, it did refer to noise filter which looks like my best option. 

Thanks about the switchfire info matzilla, i was also thinking that switchfire mode could probably help tweek it but wasnt sure which would be better.  when i was playing with the settings with my buddies unit running next to mine i did change the switchfire and i do recall it making an improvement but i couldnt remember which setting was better due to all the changes i was making at the same time my buddy was changing things on his.  it was hard to be certain what settings on mine were helping me and what settings of his might be helping mine.  I suspect settings on his unit regarding IR are likely only going to help him... perhaps if he can change his beam frequency to another khz other than 200/83 khz it might help me out?  From my reading i am finding out that most marcum, vexilar and standard flasher only units run on 200 khz.  humminbird classic flashers seem to run on 455/555 khz (if i recall correctly, or something x55 khz) and thus dont seem to interfere with other classic style flashers.  but the humminbird lcd fish finders that have ice fishing mode and can be used as flashers in the winter seem to run on 200 khz.  is it being the same frequency whats possibly doing me in?  i dont know if when i ran it in 83 khz if it was any better, but fishing that wide angle cone in deeper water is not preferable.

I also read some people had issues with having the wrong ice transducer cable for the humminbird 345c.  they had the xi 9 19 (single beam or wrong frequency i believe) rather than the xi 9 20 cable which is 200/83 khz.  I have the 200/83 khz but the thread i was reading made me suspicious of if my cable is perhaps labeled wrong, they were talking about phoning customer support and supplying the serial number to the cable and i kind of got the impression that perhaps the serial number may be a better identifier of if the cable is actually what it is supposed to be... the thread was a bit vague as to whether anyone actually had a mislabeled cable though so i may just have to call them and find out.  These people did report that when getting the right cable the interference went away while fishing next to other brand flashers.

What will manually adjustin the max depth do?  Reduce some of the noise i get below the lake bottom sonar feedback?  Give me a bigger circular graph to distribute the noise on and reduce clutter?  Or will it help reduce noise?

I think my only options are playing with the noise filter, switchfire, beam frequency (on mine and my buddies units), possibly certain IR modes on the my buddies marcum are better for noise on my unit??, and manually adjusting the max depth...

If anyone else had any ideas for settings to further reduce noise i would appreciate knowing them!  I will also maybe call humminbird about the cable and any other tips they might know.

Thanks everyone!

[3300]

when i mention beam it is the beam you get to pick from on sonars. wide or narrow beam.. wide is good for shallow and narrow for deeper waters. when you spread your beam out, it takes more strength to read the jig return ping. so you use narrow and in deep water you still at least the same area under you. example, my sonar in 10 fow is about 3.8 feet area on wide beam.

[isthereiceyet89]

I have the same flasher but I use mine in the graph mode sadly there is nothing more to do than adjust your noise filter and deal with it my buddy has an lx6 and god forbid I fish around those noisy vexilars I hear it and so does my flasher

[JZ]

use the noise filters I believe there are 5 different settings and usually one of them will do the trick although IR is the one area that HB is far behind the other manufacturers.  I have used a 345C in the past and now have a 688ci I love them both for ice fishing and open water but I dont do a lot of fishing where Iam within 10ft of another sonar.  If Iam fishing with other people we will punch a ton of holes usually atleast 30ft apart and that minimizes the interference issues.  If in a hut I can run the 688 beside a HB ICE 35 with no problems they use different transducers but a 688 and a 345 or a 688 with a vex or marcum  they dont play nice together so we just turn one of them off and position a hole to track both of our baits on one sonar.