chirp transducers

[Anonymous]

Hi
this is my 1st time on this i hope i am doing it correctly
back in late 2013 i bought 2 - 20 degree / SS264W transducers for my 8 mtr ally boat they work fine but i want to go to chirp if possible - i have a fcv295 most of my fishing is between 30 and 130 mtrs but i also want to fish the shelf over here in Queensland Australia depth varying from 200 MTRS TO 440 MTRS would the ss175 L and ss175H high frequency be the best choice - i don't think i want to with the wide as it is just to wide for my style of fishing ??
any advice would be greatly appreciated

regards morris Australia

 

[Snips]

Ridge,
Just because a transducer is "CHIRP" I wouldn't expect to have better performance than a regular transducer. Specially at a single frequency. Remember that all transducers like to resonate around a certain frequency range with CHIRP ducers having a wider range than non CHIRP. In your case you are going to be using a single frequency. Depth performance is a factor of three components; Frequency, power and beam width. The most important for greater depth is using a lower frequency followed equally by power and beam width. The 175L is capable of working from 40-60Khz. I have never tested this transducer to actually find its sweet spot or resonate point. I know from testing the 265 and 275 they like 42Khz better than 50Khz. The advantage using the FCV-295 is that you will be able to slew the frequency to see how the performance changes.

Snips

 

[rdobrow]

Snips, in your experience what do the 265's like on the High end?

 

[Snips]

rdobrow,
Because of its narrow beam width the HF side of the 265 excels in layer and thermocline detection. If you take a look at some earlier posts you will see a few screen shots comparing the HF of the 265 vs. the 275.

Snips

 

[rdobrow]

I use ff for locating structure, just wondered since the LF side has a sweet spot, 42khz does the HF have one similarly? Thanks Dick

 

[Snips]

rdobrow,
I think it works a little better in the 120-130Khz range but the FCV-295 is blocked out from 110-139Khz. Try it around 140-150khz to see what it looks like.

Snips

 

[rdobrow]

I use a very narrow beam as its a verticle game. You think the 140-150 range is better than 200-210 for discrimination? and fish on/near bottom? Thanks Dick

 

[Snips]

rdobrow,
Remember that a sounder averages what it sees, so the narrower the beam width the less averaging it needs to do. I was doing some sounder testing last week and slewed the HF frequency from 200 (left side) down to 150Khz (right side). I was in shallow water and there was no fish to look at but you can see the affect it had on the bottom return. Also another component to discrimination (resolution) is the sounders Pulse Length, the shorter the PL the better.

Snips