I have a DFF1 and an Airmar 525 TID. It seems i keep losing my numerical data in terms of the depth in my data box while I'm trolling. I previously haven't had a unit with this many options in regards to settings like TVG, etc. I have previously run my units in the manual mode and not really fishing water that is very deep and in freshwater. Anyone have any ideas for water like <80 feet. Just wondering if anyone gets really defined arches on their screen? Seems like the arches show up better in 50khz and 200.
Settings on TZT 14"
- Thread starter MikeR13
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S
Snips
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MikeR13,
Thank you for your questions.
Without see a picture of your boat, how the transducer is mounted or a screen shot of the DFF1 I can only speculate what may be going on. The digital readout of the DFF1 is controlled by a setting called Bottom Level. This setting should be set to -20 for both frequencies. If you don't have a solid digital readout none of the DFF1's Auto modes (Range, Fishing or Cruising) will function properly. Fish arches are a function of three items; fish depth, vessel speed and the beam width of the transducer. It is all about timing, the longer a target (fish) is in the beam width of the sounder the better chance you will have of it creating an arch. Arch are easier to see on 50Khz because the beam width is 3 to 4 times (depending on the transducer) wider than 200Khz. As you can see below with a 20 degree 50Khz on the left and a 4 degree 200Khz on the right.
Snips
Thank you for your questions.
Without see a picture of your boat, how the transducer is mounted or a screen shot of the DFF1 I can only speculate what may be going on. The digital readout of the DFF1 is controlled by a setting called Bottom Level. This setting should be set to -20 for both frequencies. If you don't have a solid digital readout none of the DFF1's Auto modes (Range, Fishing or Cruising) will function properly. Fish arches are a function of three items; fish depth, vessel speed and the beam width of the transducer. It is all about timing, the longer a target (fish) is in the beam width of the sounder the better chance you will have of it creating an arch. Arch are easier to see on 50Khz because the beam width is 3 to 4 times (depending on the transducer) wider than 200Khz. As you can see below with a 20 degree 50Khz on the left and a 4 degree 200Khz on the right.
Snips
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Snips, thank you I will change those settings and see how it works out. Another question I have is the other unit (lowrance) only has a few settings namely gain, colour line, surface clarity, noise rejection. I know their are similar settings on my TZT. What exactly does the TVG do?
S
Snips
Guest
MikeR13,
TVG stands for Time Varied Gain and is used to vary the DFF1's gain in the upper part of the water column.
Snips
TVG stands for Time Varied Gain and is used to vary the DFF1's gain in the upper part of the water column.
Snips
Snips thanks for your help my depth in the data box is constant and auto range is fixed. So if i increased the TVG it will reduce gain in the upper region of the column if i understand that correctly? Im trying to get a better reading down about 40-60 feet. I realize this maybe shallower than most are likely fishing. I know reducing the ping speed also helps with desired results in the depths. Thanks
S
Snips
Guest
Mike,
40-60ft is not deep, in my book that is pretty shallow. Also I would advise having the fastest ping (TX) rate possible, slowing it down gives you less information to work with.
Snips
40-60ft is not deep, in my book that is pretty shallow. Also I would advise having the fastest ping (TX) rate possible, slowing it down gives you less information to work with.
Snips
S
Snips
Guest
MikeR13,
Yes, that was an actual screen shot. What I was trying to show you was how much difference the transducers beam width can affect how fish targets appear. I very rarely adjust the TVG control(s) in waters less than 300ft.
Snips
Yes, that was an actual screen shot. What I was trying to show you was how much difference the transducers beam width can affect how fish targets appear. I very rarely adjust the TVG control(s) in waters less than 300ft.
Snips
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