Smart Troll

Down speed has never really been a determining factor, for me, when it's based on a few tenths of a mile per hour, but on the other hand down speed that pushes over a mile per hour difference from speed over ground GPS tells me a current is working against me on lure presentation, both speed and blow back depth. That information when compared has some merit, based on the visual of the lure action next to the boat at GPS speed. So for me I don't get wound too tight about a GPS and down speed being a few tenths off. Too many other factors are messing with all speed readings on rough days compared to smooth days on the water surface.

I agree with your "minds eye" that speed and drag causes depth differences far greater than worries about speed down there. Amplitude becomes greater as depth increases and also as length of presentation increases.

Depth is more critical in my opinion, in that it entails the precise location of a sharp thermocline you may be trying to target. However in that case, down temp does become more important in that it will tell you if your speed changes or your turns drops your lures into the cold zone, you now know that down speed changes depth dramatically and even more so when longer leads and deeper depths are being prowled.

Ok .....that's it...too much to say..

Mark

skipper19,

I agree with everything you said...IMO Depth and Temperature are most important. I have noticed that just wave action alone  (which causes pulling back and forth on the rods)...can affect the depth of the lure by over 10 feet.

If you have live depth data from the lure you will know when that 1 MPH situation happens because it will affect the depth of the lures by many feet.

this doesnt seem like an unbiased opinion  

bandrus1,

Guilty...I am certainly biased but I try real hard to keep that from influencing my conclusions too much. I do provide a Probe with Depth, Temp and SPEED but if you ask me I will tell you that you don't need SPEED if you have the Probes with depth and temp. The reason is because if (all else being the same) you duplicate depth then you are also duplicating speed. The Depth/Temp Probes are cheaper, smaller and lighter than the depth/Temp/Speed Probes.

Once you know how deep your setups run then you will know when the down-speed is faster because the gear will be higher in the water column than expected and if slower then your gear will be deeper in the water column.

If you adjust your boat speed to get the lure back to the expected depth then you are duplicating down-speed.

Here is my 2 cents - most if not of all the reasoning above is based on DEPTH and SPEED of the lure. My suggestion is that it may be neither or perhaps both in conjunction with a more important variable - PROXIMITY (regardless of  the above depth or speed). If the lure happens to be close enough to the fish and the fish is actively hungry or feeding and the lure appears as a vulnerable (the specific lure action) prey. The closeness also suggests the variable of minimizing energy expenditure which is also more important in colder water. Just my take on it.  Yes fish will come up to examine a lure and yes they will follow for long periods and depth of lure and speed may affect their behavior but it needs to be close and appear vulnerable and the movement of the action may be more important in their decision to bite.

Sk8man,

Bingo...I agree completely. Getting close to the fish is most important. I think the assumption is that fish often congregate in a relatively narrow layer of the water column...of course that is not always true.

But if a food chain develops around the thermocline (or in some other layer) the big fish will be there too. Or, if not too actively feeding they might seek a depth that is a comfortable temperature for them. Or whatever reason...if it is true that the target fish can often be found at a particular depth then it is helpful to find the depth where the bite is on and then target that depth with as many lines as possible.

That fits your theory exactly...get in close proximity to the fish.

You completely ignore the fact that 90 feet below the surface there is very often a current which may make your lure run at 5mph or lay dead in the water, and when a lure is pulled 10 or 20 feet behind a downrigger ball. It will not drop and significantly change its depth.

Rolmops,

I didn't mean to completely ignore that but thanks for giving me the opportunity to clarify that I am only talking about lines that are NOT attached to a downrigger. I agree completely that a relative short run attached to a DR ball will not change depth too much with small changes in speed. A few feet maybe but not 10 to 30 feet like the lines that are not attached to the DR.

The only thing that a downrigger has in common is that it enables you to target a desired depth.

If you are monitoring the depth of lines not attached to a downrigger you would know immediately if you were in the currents you described because going against that current the probe (and lure) would rise lots higher in the water column and if you were chasing the current the probe would be much deeper than expected.

If you measure down-speed in the same layer of water where your lures are found then going against the current you would slow down until the down-speed matched your desired speed and if traveling in the same direction as the current you would speed up until the down-speed matched your desired speed. Either of those would in-turn put the lures at a particular depth.

If you know the depth of the lures you can do the same thing...slow down or speed up until the lures reached a desired depth.

Been offline for a few hours but now that I am back it is great to see all of the comments. I will take the time below to respond to all of you whom have commented up to this point. I absolutely respect everyone's input so if I make a counter point please know that my attitude is nothing but positive.

I just want to keep the creative thoughts going...the challenging points all of you have made sure have me thinking it all through. So I will respond to each of you below and look forward to your responses.

Just how important IS Down-Speed

I know...many of you are thinking that down-speed is extremely important...and it is. But the question is why is down-speed SO important. In this post I will express my very controversial view just to get you thinking.

Typically when I ask why down-speed matters so much the response I get is because it affects the lure's action and I agree that it does. Certainly the speed has to be fast enough that the lure has a somewhat natural looking action but not so fast that is just barrel rolls (or comes to the surface). In my experience...while the range can be narrow for some lures, many lures look good for 2 MPH or more (from 1.5 MPH to 3.5 MPH for example). I looked hard but I could not find any manufacturer who publishes a minimum and maximum speed for their lures.

Others tell me that the fish are sometimes "just too lazy" to chase the lure if it is going too fast; or conversely "it just doesn't trigger their instinct to bite" if the lure is traveling too slow. Maybe either of these is the case sometimes...but my “instinct†tells me that a few tenths of a MPH would not typically be enough of a factor to make that much difference. If you drag the lure past the fish's nose he will usually bite (or not bite) regardless if the lure is traveling a few tenths MPH faster or slower.

When I ask what speed they troll some captains tell me they like 1.8 MPH to 2.1 MPH and others tell me if they are going slower than 2.5 MPH come help because something is wrong. The captains who troll slow catch fish and the captains who troll faster also catch fish. These guys might have some variation but typically they use the same lures, meat rigs and other gear.

One more thing...It is very common to catch a fish when the boat is in a turn. I have heard captains say if the bite is on the inside of the turn they know the fish want it a "little slower" today or if it is on the outside of the turn they want it a "little faster" today.

So, here is why I get confused when I put it all together:

• Some captains say fish slow...if you go faster the lure action is bad

   

• Some captains say fish fast...if you go slower the lure action is bad

   

• Most captains say if the fish bite the lines on the outside of a turn...troll faster

   

• Most captains say if the fish bite the lines on the inside of a turn...troll slower

   

Sometimes when I am thinking about all of this I picture in my mind...if the lure travels right past the fish at 2.0 MPH the fish will bite but troll that same lure right past the fish at 2.5 MPH and the fish won't bother. But, find any lure or diver depth chart that shows how deep it dives at different speeds and you will find that 0.5 MPH can affect the lure's depth by 15 to 30 feet or even more. Many "Smart Troll" users have proven that to be true. So, that paints a whole different picture. Now I see in my mind’s eye that if your lure is at the same depth as the fish at 2.0 MPH it could be 30 feet above the fish at 2.5 MPH (out of the zone).

When I think of it that way it makes more sense to me:

• Maybe some captains catch fish trolling slower because they have learned to get their lures at the "right depth" at the slower speed.

   

• Maybe some captains catch fish trolling faster because they have learned to get their lures at the "right depth" at the faster speed.

   

• Maybe the fish bite on the inside of a turn because they are deeper today.

   

• Maybe the fish bite on the outside of a turn because they are not as deep today.

   

• Maybe it is more about depth than down-speed.

   

• Maybe controlling down-speed is so important because that in-turn determines the depth of your lures.

   

• "S Turns" cause the lures to rise and fall in the column passing through the zone where the fish are hanging-out that day.

   

• Same with speeding up and slowing down...the gear rises and falls in the water column.

   

In the past the only way you could duplicate the depth where the "bite is on" was by precisely controlling the down-speed. But now, with "Smart Troll" you can learn to target a specific depth or temperature regardless of speed.

My mind is pretty open and I am still thinking it all through so it will be great to hear your "two cents".

The Smart Troll Probes with Depth/Temp/Speed are now available. I am happy to answer any questions.

Here is the link...  http://smarttroll.com/index.php?main_page=product_info&cPath=8&products_id=25

We also plan to release a Kayak Smart Troll kit early in May. The Kayak kit has a special (tiny) transducer that is incorporated in to a RAM mount with a 1" RAM ball. The ball attaches to a rail on the Kayak so the Transducer Mount can be attached or removed "at will". The kit includes a portable waterproof battery to power the Smart Troll Receiver. It is designed to be completely portable and light weight and it takes up very little room on your Kayak. This kit is also suitable for a canoe or Small boat.

I will take "no money down" pre-orders for the Kayak kit now...on a first come-first serve basis. Just send an email to [email protected] and express your desire to be placed on the pre-order list.

If you have any questions about any Smart Troll product you can ask here or email. [email protected]

50 years ago my grandfather showed this to my cousin and myself with a protractor, ruler, and a compass. this is why he had a fast seth green rig, and a slow rig.

different length to the leader attach point, and different leader length. different spoons, different speeds.

My grandfather loved to teach us math, and catch more fish.

Dick B.

Dick,

I have to say that your Grandfather was much better than me...I rely on a computer to help with the math.   lol

Well...I made a nice little chart that you can use to determine the depth of the DR ball. This chart assumes the DR boom is very close to 3 feet above the water's surface. The chart is based on the point where the DR cable enters the water.

The point where the cable enters the water can be used to determine the angle...which in turn can be used to determine depth of the ball.

•  6 inches back ~ 10 Degrees
• 13 inches back ~ 20 Degrees
• 21 inches back ~ 30 Degrees
• 30 inches back ~ 40 degrees

I think the chart is pretty easy to understand and use but please let me know if you have a suggestion for improvement.

Just click the link to open the attachment to view and copy the chart

Downrigger Depth Chart.bmp

Distance from your ducer to the DR ball is the depth your reading.. not the actual depth of the ball. My ducer is mounted mid ship. On low frequency will 100 ' of cable out my actual depth is about ten feet shallower that stated on my 585... I adjust in my mind accordingly. Thats why I believe running a split screen is helpful. If I see fish on both sides.. I suspect they are clost to depth im reading because the narrow hi frequency is seeing them. If only on low frequency side definitely not under the boat and up to ten or more feet different from numbers shown on screen. . If your transom mounted you numbers will be closer to actual but not exact. Phew. My head hurts

on the lam,

yep...distance not depth! If your DR is mounted mid-ship then the first several feet of cable is used just to get back under the transducer and then the sonar will show the same reading no matter what the actual depth of the ball is. Crudely illustrated in the attached graphic. And I know the transducer cone is only a few feet wide but I emphasized the cone in the attached graphic to illustrate the point.

The true depth can easily be determined if you know the angle of the DR cable and all I wanted to do in the first posting of this thread is provide a table with an easy way to determine the angle and translate that into depth. If there is interest then let me know and I can expand the table to include more information but if not then I agree with Silver Fox...we have pretty much said all one could say about the subject.

Thanks to all who contributed.

#1-Boom above water is 2.9 feet downrigger set at 135 feet td hawk gave reading 125 feet @2.6m/hr

#2- Boom above water is 2.9 feet downrigger set @100 feet td hawk gave reading 94 feet @ 2.9 m/hr

Hope this will help

Sent from my SAMSUNG-SGH-I317 using Lake Ontario United mobile app

According to the chart provided earlier...for #2  with 100 feet of line out if the ball is 94 feet deep the DR cable was at a 20 degree angle. If you measured the distance between where the cable enters the water when hanging straight down and where it entered the water when trolling it should have been pretty close to 1 foot.

I just checked for scenario #1 (135 feet of cable 125 feet deep) and the cable angle would have been 22 degrees.

Maybe next time you can measure (or estimate) the cable distance back from true vertical?

I am also curious...did you see the DR ball on sonar?

The thing I'm wondering is do you technology buffs ever catch any real fish or is it just the theoretical masturbation that excites you? A lot of folks were catching fish consistently long before most or all of this electronic gear was even invented primarily because they leaned HOW to fish.

 Sk8man,

We have fun with theory, and technology and catching fish. I guess you can say it is fun-fun-fun. It is just a matter of sharing ideas and strategies with fellow fishermen. Anyone who uses a fish finder, GPS, Chart Plotter and even a downrigger is using technology that the generation before them didn't have. We still have to learn...technology just helps us learn a little quicker. It is clear that an experienced and seasoned fisherman with little or no technology will out fish a novice loaded with technology. Nothing will ever replace spending lots of time on the lake.

I will for sure I usually troll between 2 miles/hr to 3 miles/hr this weekend will attached my td hawk and send it down and will make chart will post it

Sent from my SAMSUNG-SGH-I317 using Lake Ontario United mobile app

Thanks... Please also measure how far the DR boom is above the water's surface. If your readings help verify the chart then I will do the math to expand the chart and add more data to make it more useful to those who do not have a device to message depth.

The illustration on picture exactly happen each and every time I troll with downrigger in lake Ontario Canada I swear I am not getting any luck as I think I can see fish suspended at 120 fow I sert downrigger at 120 feet but no bite at all I just brought td hawk will try next week to see what will be the actual depth but illustrated diagram is exactly whati m dealing with

Sent from my SAMSUNG-SGH-I317 using Lake Ontario United mobile app

Adnanfarooq,

Let us know your results...it will be great to see actual measurements compared to the theory.

Good one silverfox... I will call you "sly fox" because I was pretty slow to get the sarcasm but I love it lol. The point is well taken.

Next time I will get it (I think). (;~)

That won't show you how deep the ball is. Bet you if you Troll fast enough to have lots of blowback and check the ball depth... then don't change the DR but come to a complete stop so the cable hangs straight down and check the sonar again it will read the same depth.

As I reflected on this comment I realized I had a transom mounted DR in mind. For a rail mounted DR it is a bit different because as you begin to troll the ball moves towards the back of the boat (closer to the transducer). Since the first few feet of DR cable is used just to get back to the transducer...when the ball is trailing the boat it will be closer to the transducer than when it is hanging straight down.

The attached illustration is a bit cluttered so this is a warning that it could make your headache worse...but I think it illustrates the theory OK.

Theory and math give some of us a headache and it is part of the fun to others...there is a place for all of us on the water. The main thing is you catch fish and have fun doing it.

sammyslayer...I didn't intend to pick your comments apart. Just trying to have a friendly discussion of the technical aspects of it.

Also, I just realized that the comments I mentioned above work for a transom mounted downrigger. It is a bit different for a rail mounted DR. I will post a graphic that illustrates the difference in a few minutes for anyone who is curious.

Like I said...it is just theory so feel free to pick it apart. I like friendly technical discussions.

This whole thing gives me a headache. Spitting hairs with this kind of fishing is rediculous. Your only on here to sell your unit.

Silver Fox

Hmmm...I thought I was discussing how to determine downrigger depth with a free chart. It might be a headache to you but I like discussing theory.

Sammyslayer

This is just a friendly discussion.

But it is just the opposite... a fish that is NOT directly under the boat is NOT as deep as it shows on the sonar. If you can imagine that your sonar has a ridiculously wide cone that extends all the way to the surface then a fish 1 foot deep but 50 feet away would show as 50 feet on the sonar.

When turning the outside ball appears to rise in the water column because the back of the boat swings towards it and away from the inside ball. So what you see on the sonar has nothing to do with depth but it is due to the fact the transducer moves closer to the outside ball and father from the inside ball. The sonar is reporting distance not depth.

That won't show you how deep the ball is. Bet you if you Troll fast enough to have lots of blowback and check the ball depth... then don't change the DR but come to a complete stop so the cable hangs straight down and check the sonar again it will read the same depth.

So does "Smart Troll"... but this chart is to help those who might not have either one.

Attached is a chart you can use to help determine the depth of your downrigger ball when trolling.

The depth of the ball is determined by the angle of the cable and line-out...this chart helps you to indirectly measure the angle.

The chart assumes the DR boom is 3 feet above the surface of the water. If yours is different or if you want numbers for different amounts of line-out let me know and I will add to the chart for ya.

Please note that I rounded the numbers to avoid decimals and small fractions.

The first column represents the difference (in feet) between the point where the cable would enter the water if the boat was not moving (cable straight down) and the point where the cable enters the water when trolling.

Still working on them but I won't release Probes with Speed until I develop and test a design that is reliable and consistent.

Having said that...there are plenty of "Dive Curve" charts available. Typically those charts are used to determine depth. If you know the line-out and measure the down-speed you can look on the chart to determine the depth. Those same charts can be used in reverse. In other words, if you know the line-out and Smart Troll tells you the depth then you can look on the same chart and determine down-speed.

If your setup is 50 feet deep and you are traveling with a SOG of 2.5 MPG in the same direction as a 0.5 MPH current then your down speed would be 2.0 MPH. If you turn around 180 degrees so you are now going against the 0.5 MPH current with the same 2.5 MPH SOG then your down-speed would be 3 MPH (1 MPH faster just by changing direction). Even without measuring down-speed you would know it changed because with the same setup your lure would be 20-30 feet less deep and there could be a depth change of even greater than 30 feet in many cases.

In this scenario if you slow the boat down until you achieved the same 50 feet of depth then you would also be at the same down-speed. So, you would have to slow the boat to 1.5 MPH SOG to achieve the same 50 foot depth...which would also be the same 2.0 MPH down-speed (1.5 MPH SOG + 0.5 MPH for the current you are traveling against).

Pretty dramatic...in one direction your SOG is 2.5 MPH and in the opposite direction your SOG would be 1.5 MPH just to get your lure to the same depth.

For any particular setup if you duplicate the depth then you are also duplicating the down-speed. Documented results and feedback from Captains using Smart Troll have shown that as little as 0.5 MPH change in speed will affect lure depth up to 30 feet and maybe even more for some setups.

Just thought I would follow-up to let you know users of the latest versions of Smart Troll are reporting back to me and confirming that the RPM issue is resolved and there is no interference even when using a kicker-motor.