Depth Finder Help - Pensacola Fishing Forum

Go Back   Pensacola Fishing Forum > Offshore Fishing > Offshore Fishing - General Q & A

Reply
 
Thread Tools Search this Thread Display Modes
Old 07-28-2011, 12:37 PM   #1
Member
Ruby Red Lip
 
cowboyup_iii's Avatar
 
Join Date: Mar 2011
Location: Robertsdale, AL
Posts: 56
Default Depth Finder Help

I've got a question about my depth finder. I added a Garmin 400C to the console since the sounder on my Lowrance combo unit went out. My question to ya'll is are most fish finders still able to track and mark fish/structure when underway? The Lowrance would scramble after about 7mph and the Garmin gives up after about 20-25mph. I am trying to figure out how fishermen "stumble upon" structure or natural bottom while underway from one spot to another with considerable speed. I am still new to all of the offshore tricks and just want to make sure that I am not missing something. When I'm running around 20mph, the Garmin will skip around but still be able to tell me depth but the bottom is usually scrambled making it impossible to find structure. Let me know if this is the case with all finders or if I may have some settings off. To the best of my knowledge, all settings are on auto. Thanks in advance.

III
cowboyup_iii is offline   Reply With Quote Quick reply to this message
 

Sponsored Links
Advertisement
 
Old 07-28-2011, 12:42 PM   #2
eating tasty
White Marlin
 
FenderBender's Avatar
 
Join Date: Oct 2007
Location: Pcola
Posts: 3,591
Default

Do you know what type of transducer you have? That's what actually gives you a picture of the bottom. Is it transom mounted, through hull, or shoot through hull? A 600 watt through hull transducer should be able to read up to 30 mph up to 200 ft deep. A 1000 watt through hull will read up to 500 ft at this speed if set correctly.

I don't have experience with transom mounted transducers, but from what I hear they can cavitate and get lots of bubbles in wash in the way at speed and become unreliable. If you have a transmon mount that is likely your problem.
FenderBender is online now   Reply With Quote Quick reply to this message
Old 07-28-2011, 12:42 PM   #3
Reel Insurance
White Marlin
 
Kenton's Avatar
 
Join Date: Nov 2007
Location: Pensacola, Fl
Posts: 3,778
Default

I have a color Eagle and i can run 40mph and still mark structure no problem. Has to do with the type of transducer i believe and the correct placement.

This is a transom mount.
Kenton is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 07-28-2011, 01:15 PM   #4
Member
Ruby Red Lip
 
cowboyup_iii's Avatar
 
Join Date: Mar 2011
Location: Robertsdale, AL
Posts: 56
Default

Mine is a dual freq. transom mount. I just put it on a couple weeks ago and on vacation this week in Ft. Morgan is the first time i've tested it. It marks fish and bottom fine at slower speeds (faster speeds than the lowrance would track) but after a certain speed, it will scramble and not read bottom and depth. i can agree with the cavitation causing the transducer not to read. I live in robertsdale and try to go fishing at least every other weekend, so throw up some suggestions and I can try them out when I get back out. I can't really adjust the height of the transducer (the boat is in the water full time this week). The instructions said to mount the xducer to where it is about 1/8" below the transom and I think I'm a little high but with it reading and marking fish I don't know if it is that big of a deal. would you think that the extra below the transom would help it read better at speed?
cowboyup_iii is offline   Reply With Quote Quick reply to this message
Old 07-28-2011, 01:32 PM   #5
Senior Member
Grand Slam
 
lastcast's Avatar
 
Join Date: Oct 2007
Location: Lillian,Al
Posts: 6,835
Default

Lower it and angle it slightly forward.
lastcast is offline   Reply With Quote Quick reply to this message
Old 07-28-2011, 01:32 PM   #6
EAT-SLEEP-GO FISHING
White Marlin
 
FishWalton's Avatar
 
Join Date: Jul 2010
Location: De Funiak Springs, FL
Posts: 3,949
Default

This is an interesting thread. I have the same problem with scramble above about 7 or 8 mph. I'm fairly confident the problem is caused by transducer being too close to the motor foot. Book says no closer than 18 inches. Mine is about 10 inches but did not have a choice due to way the boast is constructed and the trailer bunk is built. I just live with it.
FishWalton is offline   Reply With Quote Quick reply to this message
Old 07-28-2011, 05:42 PM   #7
Senior Member
Snapper
 
jhall's Avatar
 
Join Date: Oct 2007
Posts: 456
Default transducer

A shoot thru hull transducer will fix your problem. I just got one for about $120 and I can read the bottom at 35mph no problem. It looks like a Hockey puck and sits in a fluid filled container thats adhered to the inside of the hull. It was very easy to install and works great. No cutting and no water turbulance. That's how people are running fast and reading the bottom.
jhall is offline   Reply With Quote Quick reply to this message
Old 07-29-2011, 02:35 PM   #8
Member
Ruby Red Lip
 
Join Date: Oct 2007
Location: Pensacola
Posts: 66
Default

With a transom mount transducer, the performance is affected by turbulence and cavitation. If ANY air bubbles run across the face of the transducer, performance will suffer. These air bubbles an be caused by hull features like chines, strakes, water intakes, proximity to the foot of the outboard or the hull design itself. Anything that disrupts the flow of water. Flat bottom boats are particularly prone to this issue.

With all that said, your best bet is to mess around with transducer location. The depth of protrusion below the transom edge and into the water is pretty critical. As is the angle of the transducer face relative to the hull bottom. The aft edge should be slightly lower than the leading edge. The idea is to keep the face of the transducer in "clean" water at all times.

Thru hull transducers can help, but the flatter the hull is and the more features it has that can cause cavitation, the less likely you will be to get a clear, dependable image at speed.

Last edited by Finatic; 07-29-2011 at 02:42 PM.
Finatic is offline   Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Pensacola Fishing Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
How Did You Find Us?
Tell us how you heard about Pensacola Fishing Forum.

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




All times are GMT -4. The time now is 10:43 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 RC 2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.