Guys if any one has a helix 7 fish finder with gps no di or si needed.will hook up to me terrova us2 on the bow of my boat.so I don't need a transducer.or if anyone sees a good deal on a new one on the web let me know.seen them the other day for 367.00 free shipping on eBay for a new one.but when I had a chance to order they was sold out.my luck.thanks guys I'm from Ohio so won't need one for a month or so.in need of a cable to hook to terrova motor to.