Power supplly for fishfinder conversion to portable

[aulrich]

So the current project is to convert my Hummingbird 345c to an ice fishing unit but I am thinking if I do it right it will work both in a bag for ice fishing and mounted on the Yak. How small I can make it seems limited to power supply. I have a couple of very small 12v batteries, think a little bigger than a 2.5” thick iPhone. Has anyone used a battery that size to run a finder, or does anyone know how to calculate run time.

[mayuan]

You will have to find out what the amp consumption of the sounder is then compare it to the battery you are using.

if your sounder uses 400mA and you are using a 12Ah battery the sounder will run for about 30hrs.

12Ahrs/400mA=X cancel out the Amps
12hrs/.4=X
30hrs=X

Mine looks like this one.

http://i686.photobucket.com/albums/vv222/walleyedreams/HDSBox5.jpg

[aulrich]

makes sense, a quick google and I find out it uses 380mA I'll have to check my battery tonight.

[dodgeboy1979]

the hummingbird fishfinder i got came with the battery if you were to run it as a portable, i have the battery up here in lloyd if you want it as i hard wired it in my boat. It's just a little slim 12V battery like that would go in a flasher or underwater camera

[RavYak]

I use a 7.2 AH SLA in my kayak and it is capable of running my HB 550 or 565 for multiple days. According to Humminbird's site they only have a draw of 130-200 though. Which by the calculation is 36-55 hours which is about right with what I have noticed(never ran out but have used it up to 4 maybe 5 days without charging although usually charge every 3rd time.

[huntsfurfish]

You can find an inexpensive base to mount it on at Cabelas. On for $12.99. Just type Cabelas Sonar Hard Case into search on their site.

[huntsfurfish]

As to battery, I have some (4), 3.6Ah batteries if and when want to save some weight. But use them mostly to power Mopods and lights etc. Dimensions are 5 1/4L x 2 1/2W x 2 3/8H(inches). 7-9Ah are at least an inch(+) taller. These should all be available at a battery shop.

[aulrich]

That cabela's base gives me some ideas, should be able to knock it off easy enough with 3/4" ply I would like to keep the foot print no bigger than 6"x6", or so.

Likely the batteries I have are the 3.6, the dimensions sound about right.

That' is only 9.5 hours, i'll have to jump up in size I think. but I do have 2 of them.

[RavYak]

If you have 2 3.6 hour batteries then just use one at a time or hook them up in parallel and should be good enough, just have to remember to charge after a long days use.

[iliketrout]

Don't forget the batteries won't last as long in the cold as the ideal calculations would indicate. My HDS5 setup similar to Mayuan's will run about 8 hours on a fully charged 12V 7.2 aH battery if I keep the battery up off the ice and the screen brightness at around 3-4 (out of 10).

Thinking about building an insulated case for the battery this year.