MFD8 fish finder settings

[Anonymous]

I recently purchased and hooked up a MFD8, DFF1, and an AIRMAR 1000watt in hull transducer.
I frequently fish a buoy that's located on a 1000fathom ledge. I am trying to figure out all the settings that I need to input on my MFD8 to see the fish that are usually in the 25-35 fathom range below the surface. I have tried different settings although I cannot see any fish or markings on my screen, besides the clutter near the surface of the water. Does anyone know how to set up the settings on a MFD8 for this type of fishing? When I go bottom fishing where the water is 25-150 fathoms my MFD8 works like a champ. However at the buoys I get no such luck. Do I have to set my TVG setting? I dont know? Im clueless? Btw, I know there is fish there at 25 fathoms because I catch them, I just cant see them on my MFD8 fish finder screen. Please help. Any suggestions would be greatly appreciated. Thanks .

 

[Snips]

Casey,
Thanks for the question. When you say a 1Kw in-hull I am assuming you mean a M-260, correct? When you are looking for these higher water column fish what frequency are you using? Do you have any screen shots you can post so I can see what you are looking at?

Snips

 

[Anonymous]

Hi Snips, yes that is correct. I have a M 260 AIRMAR. I have tried both LF and HF settings as well as the dual screen feature, with no luck. Is it possible that the fish is moving too fast? Can you explain to me also the settings for the time intervals setting e.g. 1/1, 1/2,....
Sorry I do not have any pics at this time. The screen is shows clutter at the top and the rest is just blue with the depth interval markings on the right side.

 

[Snips]

Casey,
The screen advance rate is a combination of two things. Screen advance (movement) vs Tx rate. So a 1/1 mean the screen advances one division every time the sounder transmits. A 2/1 mean the screen will advance two divisions every TX pulse. So even though the screen is advancing faster it is stretching the displayed returns, which can lead to blocky returns.

Snips

 

[Anonymous]

Thanks Snips, so is it better I leave it on 1/1? Sorry if that's a dumb question but I'm clueless haha.
Also can you explain to me the TVG settings? What is this for?

 

[Anonymous]

For finding fish in the 25-35 fathom range while floating in 1000fathoms of water, what are the important things to do on my settings?

 

[Snips]

Casey,
TVG stands for Time Varied Gain. It is used to vary the sounders gain in the upper portion of the water column. On the DFF1 the lower the setting, the less gain you will have close to the surface. Below is an example.

Snips

 

[Anonymous]

Oh ok. Thanks.

 

[Anonymous]

Is there a way to adjust the range to see only what's above 40fathoms in 1000fathoms of water? Is there a range setting?

 

[Snips]

Casey,
Just set the MFD-8 for manual range and you should be able to find a range that is very close to 0-40fm.

Snips

 

[Anonymous]

Thanks snips

 

[Anonymous]

Thanks snips, I set to manual range adjusted to 0-40 fathoms and saw the colored blob of fishes hanging at about 20-25 fathom. Thanks!