DFF1-UFD clicking

[sdonx]

I just noticed this when searching for another issue.
I hear a clicking that i never heard before. It must of become louder than it was.
Also at some point during our last trip i have horizontal lines show up on my side scan view?
Related?
Normal?

 

[sdonx]

New info. When i shut the DFF-1-UHF off the lines disappear.
Bad transducer?

 

[gtstang462002]

Sounders click, most of the time they are inaudible, yet once you start to hear them clicking, you can't un-hear them. My suspicion is that the lines that you are seeing go away are just interference from a neighboring sounder that may be ringing on a close frequency. What is the mounting arrangement of all of your sounders in relation to each other? What type of boat? Any photos that you can provide of everything that is mounted would probably assist greatly with getting to the bottom of your issue.

 

[sdonx]

You can see the sidescan mounted on the keel. The transducer that you see on this side is the DFF3D.
The Chirp transducer is located directly on the other side of the keel, a little closer to the keel from the DFF3d.
The sidescan is back about 2 feet from these.
The sidescan is operating at 230kHz and the Chirp is at low I believe, with the DFF3D at 165 kHz

 

[gtstang462002]

I have almost the exact same layout. What is your CHIRP transducer? You mention that the lines are going away when you stop transmitting on the DFF1-UHF which would lead me to believe that your CHIRP downscan may be ringing in the 230kHz range also keeping in mind that this sidescan is also a CHIRP transducer. I do not know what the CHIRP range is for the sidescan though. My B275LHW for example has a HF CHIRP range of 150-250 kHz. I am seeing some of the same lines that you are but have not really had enough time using my setup to "tune it out". You can try setting the interference rejection to "High" as opposed to "Auto" which would be my first suggestion.

 

[sdonx]

B275HLW, maybe its on high not low. I will adjust high down to 220 as a max. Is 10* seperation ok or should I have more?

 

[gtstang462002]

I would think that it should be enough. I am not an acoustics expert by any stretch of the imagination. That is better left to @Deep Blue for full clarification.

I believe that when the sounder is transmitting, it transmits both high and low frequencies concurrently.

 

[sdonx]

Down scan max is 225 kHz so thats a 5* seperation. I need to research more on how to lower, it was not something I could find.

 

[gtstang462002]

You pick your center frequency and then set your frequency bandwidth to cover that. A simple test rather than adjusting your CHIRP settings your be to run your sounder in CW mode (single frequency) to see if the lines stop while it is still firing. That would limit you to 50/200 on the Frequency and create a full 30 kHz of separation.