Sounder Question...

[kiro]

Hey guys...

looking for a fishfinder, and i have some questions.. what does 'dual beam' mean, and wat does 'dual frequency' mean??

which is more essential for me to have in a fishfinder??

and can somebody please explain in very simple terms what is meant by 200khz and 50khz? and also what is meant by the different angle degrees??

pretty much, can somebody please explain to me how these bloody things work? no idea... i just want to know where the fish are underneath me...

thanks heaps fellas.. appreciate it..

kiro

p.s - i dont go way offshore or anything like that.. and i'd need it for a kayak... if anyone has any recommendations, that'll be great!! cheers

Edited March 12, 2009 by kiro

[michaelrdoyle@gmail.com]

looking for a fishfinder, and i have some questions.. what does 'dual beam' mean, and wat does 'dual frequency' mean??

which is more essential for me to have in a fishfinder??

and can somebody please explain in very simple terms what is meant by 200khz and 50khz? and also what is meant by the different angle degrees??

....

p.s - i dont go way offshore or anything like that.. and i'd need it for a kayak... if anyone has any recommendations, that'll be great!! cheers

Not sure about "Dual Beam" - could be the same as "Dual Frequency".

"Duel Frequency" - means the transducer will work on two frequencies. This is because different frequencies work best in different circumstances.

As you've already pointed out, most duel frequency sounders work at 50khz and 200khz. If I remember right, 200khz is best for shallow water - up to perhaps 100meters (check that). 50khz works best at very deep depths.

Angles: The angle basically measures how wide the beam is. The wider the beam, the more it shows you, but the less effective it is at greater depths. The 200khz beam has a wider angle on the sonar beam. The 50khz is narrower. So the 50khz is better at big depths, but will only show you what is directly under the boat.

Since you will be on a kayak, you want single frequency - most likely around 200khz (not sure what the options are). I reckon colour is awesome - made a big difference when I moved from B&W to colour.

Good luck.

Mike

[Captain Spanner]

I'm no expert but from what i understand dual beam means there are 2 settings that can often be run one at a time or together. It is like having a flood light setting in a torch (wider area in shallower water) and spotlight setting (narrower area but goes deeper/further). My old Hummingbird Wide eye has this and if you have it on wide mode it loses the bottom at a certain depth (can't remember what, maybe around 50m) and if i switch it to dual it gets a bit deeper and narrow mode even deeper.

I think the dual frequency is a similar concept as described by Mike.

Hope this helps.

[glennmreid]

Dual frequency means the fishfinder can run on two different frequencies depending on what detail and depths you are fishing. My Furuno FCV 620 has dual frequency 50 khz/200 khz. The 50 khz has a wider beam and shows more, but at a lower resolution so is more suited to shallow/medium depths. The 200 khz frequency has a narrower beam, shows detail in a higher resolution. The beam is narrower so goes to deeper depths, so it more suited to deeper water. On most dual frequency fishfinders, you can when both frequencies at the same time to compare the readings. Below is a copy of my fish finder manual, showing you the two different frequencies, and the beams associated with dual frequencies.