khz

[fishsniffer]

alright...so im floating around muskegon,just burnin gas,so i start monkeying with the new graph...do you guys run 50khz,200khz or do you leave it on auto?what are the pros and cons to the different khz?

[1mainiac]

How in depth do you want to get Don? There are many variables depending on cone angle and freq that come into play. 50khz is a longer wavelength freq which means it will travel further per cycle roughly 600 meters per cycle where 200khz is faster and shorter roughly 150 meters per cycle. At the same cone angle 50khz will read deeper into the water but 200khz will have 4 times as many returns so more detail. Most current fishfinders use a wide cone angle on the low freq which will give you a bigger picture of the bottom and often pick up your cannonballs better but again less detail. And use a narrow cone angle on the 200khz to give you better detail and hold the bottom better at speed. My Lowrance uses 200khz for fish id and 50khz for the fish alarm this is often annoying as it picks up the cannon balls in fish alarm and rings all day long. Personally I think I would prefer the 200khz to be wider but I am thinking that is now called side imaging or at least a variation of it. For most of the water I fish in I would rather have a wide 200khz for fishing and a narrow 200khz for running in and out as we seldom see deep enough water to need 50khz in narrow mode like ocean going ships use and we all pretty much run much faster then those ships as well. As such I seldom use the 50khz on my finder once in a while I will run it in dual mode to look a little wider but I use 200khz 90% of the time and have never put it in auto mode.

[Hotdog71]

Don,

According to my manual, the 50 khz is for a wide cone of the water and the 200khz is for deeper water fishing narrow cone with better bottom resolution. The 50khz will give approximately 20 ft of coverage at 30fow while the 200khz will give 6ft of coverage. This is all determined by your cone angle. My 50 is a 40degree cone and my 200 is a 10 degree cone.

Personally, I use mine at 50khz under 50fow and either the 200khz or use the dual feature in the deeper water.

Hope that helps.

Bob

[GLF]

I run the 50khz in the shallower water, and the 200khz when I am 80' or deeper. When I am running out, I have it set on 200khz, and it does not loose contact with the bottom.

[inreeltrouble]

thanks for asking that question Don. I have often wondered the same thing but can't always remember to ask questions like this one, until i'm on the boat wondering???? Man i need to work less and fish more so that i'm only thinking of fishing.. ha ha

[Willie Bee]

If you can run the dual transducer or just learn to flip flop them, aside from holding a bottom reading at higher speeds, you can dial in the gain to see your downrigger balls which aids in blow back calculations. Then if you play with more buttons and it is in color you can mark temp breaks at depth and if your running short leads on the riggers you can watch the fish bite and the fish that just miss the downriggers lures.