Avon Rover 3.4 sib fish finder

[DH1]

Hi to All,

I am tempted to buy a handheld fish finder for my sib but have a few concerns as follows:
1/ How accurate are they ? On depth & boat speed.
2/ Can the transducer be mounted on the rear of the transom & does the wash from the motor interfere with it (10hp) ?
3/ Whats the best one to get ?
4/ Are the fish finding capabilities really worth it ?

Any advice would be much appreciated, was thinking of the Garmin Striker 4.

Thanks, Dave

[Blankton]

I have a garmin striker 5. I didn't screw directly to the transom, I made a bracket that I could fasten to the hole already there for the towing eye using a bolt and wing nut. This way I could remove the transducer and wiring from the boat each time I packed it away.

It wasn't affected by the propellor and gave what appeared to be accurate depths even when planing. The bracket held it right by the tube, so as far as possible from the motor.

It could definitely see fish and features on the bottom. Best used with navionics on your phone, so that you find the rough location of the reef using the GPS, and then look out for the exact position on the sonar. However, I would say that just because you can see the fish, it doesn't mean you can catch them. It often shows up big balls of fish for me, but they may be tiny sprats or sandeels, so you can drop your bait into them, but not catch!

A 1lb wrasse swimming back to the bottom:




A thornback Ray swimming down in quite deep water:




Working feathers through a big shoal of nothing! The feathers are the horizontal line, so you can see the depth you are at compared to the fish. In this instance I didn't get anything. The "mark" was maybe small fish.

[tinker]

Interested in this for spearfishing, looks like it could be useful. How do you power it?

[Blankton]

It's powered with a battery. Obviously on a rib or bigger boat you'd have a battery for the starter motor and nav lights. On a sib you generally wouldn't have a battery as standard.

You can buy small batteries from Screwfix. This was my solution:



Battery fitted in a waterproof accessory box. A charging lead and the power lead for the fish finder were fed through a grommet.



You can see in the photo below where I clipped the battery under the rear seat, completely out of the way. The fish finder backet was on the rear seat.



I've also seen people make battery cases out of those waterproof pelicase type things. With that arrangement they have fitted the bracket to the top of the case, so the whole fish finder and battery is lifted out in one go.


This is the bracket I made that clipped over the transom and fastened through the tow hole.

[paintman]

The batteries shown above are usually fine with fishfinders.
I use a slightly larger one of the same make with my Dragonfly 7 at Rutland Water & Pitsford Water for pike fishing from their hire boats.
The screen is fastened to a bit of board I bungee to the seat & the transducer over the stern on a long piece of wood held onto the boat with a G clamp.
Full charge lasts at least two days.

[Blankton]

Originally Posted by paintman

The batteries shown above are usually fine with fishfinders.
I use a slightly larger one of the same make with my Dragonfly 7 at Rutland Water & Pitsford Water for pike fishing from their hire boats.
The screen is fastened to a bit of board I bungee to the seat & the transducer over the stern on a long piece of wood held onto the boat with a G clamp.
Full charge lasts at least two days.

That battery I've got lasts a day, its never run out on me. If I make another I might use a slightly bigger battery so I can have a phone charging socket, as navionics seems to destroy my phone battery.

I've already touched on it, but for fishing I think navionics is essential. Probably more useful that the fish finder, so if you only have space or money for one thing, I'd get navionics.

[DH1]

Hi B,

Thanks for this. I was thinking of getting the Garmin striker 4 as I think it has integral chargeable batteries that I’ve read can last a day ? As well as the fish finding, it also gives your speed and depth which could be handy for obvious reasons, although it would be good to know how accurate the depth detection it is in shallower water (around rocks) and also how accurate the speed is ? Were instructions included with the transducer ? Was just wondering how deep it has to go below the water or hull or prop ? Ta

[tinker]

Blankton, great post like the battery idea , just got to get Xmas expenses out of the way

[Steve509926]

Hi Dave, I think if you use the forums search function you will find lots of useful info.

Although I don't use my chartplotter /fishfinder for fishing, you may find the following thread helpful-

https://www.rib.net/forum/f37/not-fo...ing-86842.html

[Blankton]

Originally Posted by DH1

Hi B,

Thanks for this. I was thinking of getting the Garmin striker 4 as I think it has integral chargeable batteries that I’ve read can last a day ? As well as the fish finding, it also gives your speed and depth which could be handy for obvious reasons, although it would be good to know how accurate the depth detection it is in shallower water (around rocks) and also how accurate the speed is ? Were instructions included with the transducer ? Was just wondering how deep it has to go below the water or hull or prop ? Ta

I don't know of that model, but if it has internal batteries that would make things simpler. Battery tech is improving all the time, so it may well be the case that they are doing that.

Regarding depth, I have gone up some very shallow sandy creeks. It was quite predictable that the prop would start to kick up the sand at about 1.2ft depth. This was quite repeatable, so in my mind it seemed pretty accurate.
I wouldn't be going that shallow with rocks though, as a rock in itself might be 10ft high! If in shallow rocky ground, you really need to stand up and look around you. Often a good area for bass, so I have been known to drift into those kind of places!

There will be instructions for mounting the transducer. It wants to be about flush with the bottom of the transom. But if you were a couple of Inches higher or lower it would just mean the depth the unit showed was a couple of inches deeper or shallower. It wouldn't become a problem unless you were so high that you started blocking the signal with the transom or picking up interference from the engine.

[paintman]

Bear in mind the usual positioning of the transponder on most fishfinders will show you what you've just passed over, not what's coming up in front of you.

For that you would need something forward facing & even then you should approach hazards slowly just in case & you would be best to have a chartplotter to help you stay away from sticky up bits.
You might want to have a play with the Navionics app with the overlays as this is very good on your mobile if you don't want the expense of a chart plotter.

I do quite a lot of bass plugging in shallow water over rocks & need to keep a sharp eye on falling tide height as many will be above surface at lower tides. I wouldn't go onto those areas in any sort of wave/chop.

Hitting the bottom with the prop - even soft - isn't advisable as you're likely to draw whatever is kicked up into the cooling system. Plus you have no idea what might be hiding in the sand/mud.