50kHz versus 200kHz question

[JimRK]

I am currently researching which electronics to buy, and have a question I hope someone can answer. The 50kHz frequency is suppose to be for deep water applications and the 200khz for shallow water. I would think for deep water you would want a narrow cone and for shallow water a wider cone. Yet with the Lowrance dual frequency transducer, 50kHz is a 37 degree cone and the 200kHz is a 12 degree cone? I also noticed this with some other manufacturer's products. Any technical reason for this configuration would be appreciated. Bewildered!! Thanks

[Lund_Dude]

The high frequency is used for deeper water. The higher the frequency, the better the signal penetrates the water.

[saskfish]

The Garmin fishfinder 160 blue comes with a 50/200 transducer. I believe the reason is that depth and contour change are seen as being more important in shallow depths than locating fish. A wide cone(50khz) may miss subtle changes as only the first return from the transducer is displayed. I think this is why but I may need some more explaination as well.

[Brad]

The low frequency (50 kHz) is definitely for deep water applications. Lowrance (www.lowrance.com) has a pretty good explanation as to what frequencies and cone angles should be considered for different types of fishing. Try logging onto lowrance's homepage and looking around for a description of these technologies.

[Seagull]

The reason the 50khz transducer is better for deep water or saltwater is the operating frequency. I don't know what unit you are interested but I would strongly consider the use of the 200khz transducer if you are a freshwater angler. The dual frequency transducer for the current Lowrance product does not perform well for Walleye/Smallmouth type fishing applications. I strongly advise anyone purchasing an X-15/X-16 to purchase the single, 200khz,20 degree x-ducer. If you fish the Great Lakes for Salmon and wish to view your downrigger balls, the 50khz might be a consideration. Choices...........................

[Hawgeye]

The 50kHz frequency is for deeper water applications due to its larger/longer wavelength which penetrates the water better allowing for a deeper reading. The 200khz is shorter wavelength and is absorbed more easily by smaller objects not allowing that penetration. In my opinion, the 50 khz transducer is not necessary for walleye fishing.

[Larry]

The 50 Khz tansducer w/ wide cone angle is exactly what you want for salmon/trout. It covers a wide area of deep/open water and can help track the D/R balls. If you happen to be running the 350A, the dual freq transducer is a plus that allows you to run both freqs at the same time on split screen. For salmon/trout, I like to run my X70A off the 192 Khz transducer using full screen and the LMS350A on 50 Khz, also in full screen and w/ no interference between the units.

This becomes a bit confusing when you look back at some of the earlier flashers for shallow water that ran 32 degree transducers at or near today's 192Khz. The idea being that the wide cone angle would "pick up lots of stuff".....it did BUT it was real hard to follow a break line or weed edge. You were better off with the narrow cone angle.

[JimRK]

Thanks everybody for your input. Happy fishing!!!

[anxious]

i have posted this b4,i think that a lot of people bought into the dual trans option because they want everything thats available for the unit they are buying. and im sure that some of them need the 50khz unit but for the most part would be just fine with the 200. i wonder if some of the problems the x-15 is having is with the use of the dual trans? i have the single 200 and havent had any problems so far except with reading the navionics maps and that problem has been fixed!