Depth finder question

[Bill B.]

How waterproof are modern depth finders? If I put a Helix 5 on my kayak, for example, what will happen to it when I roll the yak?

[moguy1973]

According to Cabela's website the Helix 5 is waterproof.

http://www.cabelas.com/product/HUMMINBIRD-HELIX-SONAR-GPS-COMBO/1925187.uts

[jdmidwest]

There are several types of waterproof. Fishfinders are waterproof against a driving rain. I don't know if they test for submersion or depth submersion. Depends on what the rating is. 

[moguy1973]

I just read that my Garmin 73sv is waterproof to depths of 1 meter for 30 minutes.

[jdmidwest]

My buddy dropped a Magellan GPS unit out of the duck blind one morning.  When he retrieved it some time later that morning, the waterproofness had failed.  I think it was rated for 1 meter and 30 minutes.  It was about 4 foot deep and sit there for a few hours.  Of course, it was on and running when he dropped it in, so it fried when water leaked in.

[Bill B.]

Sounds as if I'd have a decent chance of recovering it undamaged if I immediately got it out of the water. Thanks.