# Humminbird 1159c & 997c SI



## waterboss (Aug 16, 2010)

Ok Folks

I have a 997c si now on the boat.........my question is this.

Will I have to change out the transducer if I upgrade to a 1159c ? 

I will change it out if I have to, but I would rather not.


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## papaperch (Apr 12, 2004)

If you are upgrading to a 1159 they would use different transducers. Because an 1159 is not a side imager as your 997 is. But if you are upgrading to a 1199C the transducer would be the same.

What is confusing me a little I would not consider an 1159 an up grade. A 1159 does have down imaging but not side. Course you would have bigger screen but side imaging is a must have to me. 

I was thinking that perhaps you meant to type 1199. As a 1199 would be an upgrade in every circumstance.


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## waterboss (Aug 16, 2010)

The 1159 is the unit and to me it is an upgrade from the 997c because of the larger screen. I never use the side imaging feature, so it really is of no use to me.

Will the transducer for the 997c even work with the 1159? or is it not even compatible?


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## papaperch (Apr 12, 2004)

According to Humminbirds website the 1159 is not listed under the transducers units.

If you do use the Down Imaging the crystal in the 1159 transducer is a dedicated crystal for the down imaging. So changing the transducers would greatly benefit you.

You could hook it up to your present transducer to see how it would perform but I doubt you would be satisfied. Is the wiring run in your boat make it difficult to do ?

If you reside in northeast Ohio I could assist you if you need.


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## OldSchool (Oct 18, 2006)

+1 on what PP said. The SI units simply reprocess the signal and paint the screen with a DI look - no new info added. Since DI is apparently what you want you should go with the DI transducer.


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## legendaryyaj (Nov 1, 2005)

The 997 transducer should work as the unit itself does DI and SI. It should be a better transducer than the DI only transducer.

Is there a reason why you don't use side imaging? It's the best thing since sliced bread.

I agree with PP that it's not really an upgrade technically. If you just want screen size then why not get the 1199?


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## steelneyes2 (Jul 19, 2011)

I have a 999 and an 858 and the 999 transducer will not read on the 858 DI. It does give DI when I feed it via ethernet but not when hooked directly. If you are straight up replacing the unit then you will have to change out the transducer too. 
I guess I'd have to agree that if you are going for a bigger screen, stick with the SI, you will get your money back in resale if not anywhere else, and save the time of re running and installing the transducer.


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