pr7763
02-24-2004, 06:25 PM
bought a fishhawk 1850 and i want to put a locator on the bow and dash to run at the same time. they all seem to be 200khz. does that mean they will interfere with each other? also what would you get x100c or x125 or which garmin unit. color worth it??
Unfortunately, they will interfere with each other, but talked to a guy from lowrance who said their new models come with an adjustable ASP which is supposed to take care of this.
The reason you get interference is very similar to a 2 speaker stereo system. If you were to have both speakers spread apart, but facing the same direction, you could walk across in front of them at a distance and you would hear some really loud spots and some weaker spots. This is due to the wave paths crossing each other. at some points the waves actually work together and amplify, then at others, they will cancel each other out. The same thing happens with transducers. If the frequencies are different, there is still going to be interference, but not as much since the wave paths are different. The less interference, the better the signal from each transducer.
Keep in mind, though, that you will only get interference when the cones cross paths. If you are in shallow enough water, the cones will not cross, and no interference will take place.
I took a look at this with my boat. I happen to have a 16.5 footer, and with most 200khz transducers, they have a 20 degree cone angle. By basic trig, the cones would not cross each others paths until I am over 47 feet of water. This is assuming I have a trolling motor transducer for the front, and the transom mount transducer on the back, separtating the transducers by the 16.5 feet. I am guessing that if you are planning on putting a transducer on the bowmount, there really is not too much to worry about, unless you fish really deep water.
As far as the two units you mention, I am unable to help there....I have no experience with them.
Steve
pr7763
02-25-2004, 02:45 PM
thanks for the answer i just don't understand why all the manufactures use 200khz when the know most fisherman have 2 graphs and would have interference