295 and confused

[Anonymous]

Hi
I have a Fcv295 connected to a airmar 109RLHW through hull . Mostly targeting bottom fish between 30ft to 200ft . 295 settings on HF ( 200 khz )are transmit rate 20 , TX at 10 and gain usually around 3 .
I have a fcv585 with b45 (600w) as my old sounder still going as a comparison
Now the confusing part in shallow water ( 10 to 60 ft ) the 295 picks up fish really good nice archs ( red/orange ) and definition really pleased with its performance and hands down beats the 585 for performance .
But when I go deeper 150 to 200ft the 295 under performs compared to 585 .
295 still has good solid bottom signal with no breaks in it but the fish marks are weak and fractured no deep red colours but broken greeny/blue marks , turn the gain up and dosent seem to help
585 showing better fish marks at this depth .
I have the 295 on HF short pluse to try and get the best definition of fish living close to the seabed and at only 200ft should have plenty of power to still mark fish well
Have been trying for 10 months to solve problem .
Help Confused
Cheers Visky

 

[Snips]

Visky,
Do you know that the R109LHW uses a 1kw element on the HF side? This plus the beam width is twice as wide as the HF side of the B45, this mean that actually the HF side of the 109 is putting less energy on the target at 200ft than the B45 does. In my testing I have found that the wide HF side performs best in shallower waters. As you can see in the target detection comparison below, the B-275 uses the same element as the HF side of the 109LHW.

Increasing the pulse length will help a little bit, but have you trying using the LF sidem of the 109? The LF side will return harder but shorter targets because of it's narrow beam width.

Snips

 

[Anonymous]

Hi Snips
Thank you for a quick reply
The fish I am targeting just about live in the mud bottom and was hoping to use a HF to give the best definition of fish from bottom .
585 with the b45 I was on LH (always on LH )
I will try some of your suggestions and let you know how I get on.
Thanks Visky

 

[Snips]

Visky,
One other tip that might help is using the FCV-295 on a MAX TX Rate when using LF. This shortens the Pulse Length so it may help when looking for fish that are tight to the bottom.

Snips

 

[Oetgreen]

Hello Snips!

I am interested to buy same transducer (R109LH or B260 or B265LH) as an author of topic, and I find that there is the modification of this transducer R109LH "Wide" ( B275LHW for B265LH). As well as Whisky I need to find fish closely located to the bottom in 60-200ft. (Rarely 400-600ft).

Tell me please - can I have any advantages using "WIDE" transduces? Does the high power R509LHW give me the better bottom fish image than R109LHW?

Thanks!

 

[Snips]

Oetgreen,
The difference between the R509LHW and R109LHW is only in the LF side. They both use the same wide HF element.

I don't think either are needed in that shallow of water. Look at the below screen capture of another B-265/275 comparison.

Snips