Humminbird Helix9 SI sonar stopped working

[Bobinette]

Putting this out there to save some frustration for some of us and maybe some cash as well. I blew a board in my 1 year old unit about a month ago. Sent it up to North Bay for warranty repair and afterwards when I asked why this could have happened I was explained by the tech something that`s not even in the manual, which is pretty basic to put it mildly. So the problem stems from having a side imaging transducer which due to it`s shape tends to lose contact with the water at higher speeds. When this happens the unit tries to establish bottom contact. Because factory setting for "MAX DEPTH" is AUTO and if you're like me you leave this setting alone, as the unit tries to reestablish bottom contact it will keep increasing the strength / wattage of each ping thinking that it must be in very deep water, it eventually will ping so hard that it fries a few diodes on some of it's circuit boards. Crazy that there's no limiter of some sort but that's how it is. The remedy can be one of 2 options. One is to add a second, high speed, transducer and a Y-cable connection thus this high speed transducer is always in the water and no loss of bottom contact. Two, this is what I did, is to limit the MAX DEPTH setting on the main page (press MENU twice) to say 300' which is more than enough to cover the portion of Lake O that I fish and by doing this the unit will only send out strong enough signal it would need to get through 300' FOW, never frying itself again. 

Hope I explained it clearly enough to understand, PM if I can answer any Q's.

Cheers

[Sk8man]

I don't have a Humminbird unit but I think you described the issue very clearly and it may save some other folks from headaches and it is really to your credit for taking the time to let folks know