hummingbird question

hi all new to the site.....right now I have a older (basic black and white)hummingbird 550 fish finder I want to up grade, looking at 581 I HD(black and white) sonar / gps(do I need a gps...for maps...don't no) and a 576C HD DI sonar color (NO GPS) (I think I want the down imaging) . right now I have a shoot thru ducer with the 550. if I up grade to one if these and it has a transom ducer can I install and use it as a shoot thru ? I really like the color screen and probably see thing a little better. now since these are all 500 series are the heads interchangeable with my 550 existing wires? what do you all think ,did you have to think about this before buying? glenn

Glenn,
The transducer that you have installed for your 550 will work with the 581i Combo unit but it will not work for the DI model unit. However, the transducers that come with both units may be installed inside-the-hull. Just use a good quality slow cure marine grade epoxy to do so and follow the proper procedure. I’m at home so I don’t have instructions to send you but I believe that they are on the Humminbird web site. If not, just shoot me an e-mail and I will send them to you when I get back to work tomorrow.

GPS with a B&W display or DI with a color display… I like the color units more than the B&W but if I ever thought that I could be in a situation where I needed GPS to get back to the landing safely, I would have to go with the GPS unit. I’ve been in several of those situations on a lake that I have boated for 20 years, so don’t think that it cannot happen, but this was for work so I didn’t always get to pick and choose when I went out on the water either.

You asked if you needed GPS for maps....if you mean you want to install a map card, I would think the GPS would be necessary. I can't imagine using the map card without the GPS. All you would have is a map of the lake, and it would be cheaper to buy a paper map than the card.

hi vic.....I know I would need a card with a GPS for lakes , what I meant was do I personally want one or try to buy a unit with only color and down image only... do they make one with color and DI only?

Glass boat I presume. I use the GPS more than the sonar. I love my 597 but Brian and shut up and fish are practically giving the 788 away and it has it all. It is cheaper than my 597 was a month ago. The 2 card bays are much better than one. Twice as handy.

I also vote for the on sale 788. Got everything you need and some. Like Gomer said, practically giving it away. If I had the extra money would buy one and don't need it.

if you get the 788 and the best of both worlds you can probably take the new mount put it up front by the troller use the exsisting mount at the dash and get your gps and sonar. then put the di transducer up front on the troller and just switch it when you get to your fishing spot and get better pics of what is going on down below. just my :twocents
worth