DB
Darn good idea. 
Option 4 : 1 X 10 = 10 Energizer D     14000mAh $12.50 for one trip 3Lb
I have been told that Duracell are better than Energizer but I have no test data to back that up.  Never tested C cells so don’t know how that would work.
I was told when I was a kid that if you put a bumble bee in a jar with some rocks so it would sink it would attract fish.

ST
Because of the weight-hassle factor I have never considered solar rechargers for a canoe trip. My daughter did some work on a material that could be used as a display device and solar collector.  So the fish detector of the future could charge its own batteries.  What I am reading about solar collectors is the push is on to get the most watts out per dollar invested at the expense of watts out per pound and square inch.  This will make solar collectors on your house profitable but it may sink your canoe.

Spent a couple of nights on Kashakokwog.  I was cleaning the groups fish on a rock away from camp.  My back was killing me so I was hurrying up to get done.  When the fillets were removed from the first fish I threw the carcass as far out in the water as I could without looking up.  When I finished the next fish I did the same thing only the sound of the carcass going splash was replaced by the sound of an eagle just over head.  I looked up to see the eagle carrying the carcass away.  The eagle had timed it perfectly to catch the carcass before it hit the water.
Hope you like Kashakokwog as much as we did.

I have kicked around the solar panel idea for a while but from what I have read is that direct sunlight is what makes the difference. For example here in Florida might work out pretty good but my suspicion is in the northern climes perhaps not so well with often less than direct sunlight.

Good luck ST on your trip, I have a good feeling for you that the fish may be quite a bit more cooperative for you than your earlier venture. Enjoy yourself.

MT

Need ideas and photos of anyone who has (successfully) mounted a transducer out side of the hull. I have the suction cups but the transducer gets tweaked from the water current or just falls off.....I can't shoot through the hull as I believe the northwinds has a foam core...

HighnDry wrote on Jul 31^st, 2018 at 2:34am:

H&D
It is true that a transducer does not shoot through foam care well at all but you can go around it.  NorthStar canoes have a cut off diamond shaped foam core in the floor of the canoe.  I have a NorthStar Polaris with the same floor as the Northwind and I mount the transducer behind the back seat just off of the foam core.  Works well. I use plumbers putty and it takes me about 10 minutes to switch it from one canoe to another. It sticks well enough that it has never fallen off in many trips to Canada and back but it is easy to remove to put in another canoe.
MP