Black Box ?

[Kisinana]

You need a voltmeter which will read millivolts DC. Set the meter on this scale and attach one lead to the negative of your boat and the opposite lead to the downrigger wire. If you happen to have the leads backwards the value will show as a negative.

SPECIES VOLTAGE
Chinook (King) Salmon .600 volts
Coho (Silver) Salmon .650 volts
Sockeye Salmon .750 volts
Kokanee Salmon .650 volts
Halibut .450 volts *
Laketrout (Mackinaw) .650 volts
Rainbow & Brown Trout .650 volts
Cutthroat Trout .650 volts
Black Bass .750 volts *
Sharks .400 volts *
Striped Bass .650 volts *
Sturgeon .500 volts *
Catfish .500 volts *

* Further research may change this recommendation

In the June 1991 issue of National Geographic, researcher Adrian Kalmijn noted that a “shark recognizes an electric field in the order of five— billionth of a volt per centimeter.” Kalmijn offers this perspective. “Plant electrodes 2000 miles apart on the ocean floor and power them with a 1.5 volt flashlight battery. That is a very weak electric field. But every shark in between those electrodes will know what you are up to.”

 

[Yote]

ok, so what about the other 400 boats around you that don't worry about it.

 

[teamchachi]

The biggest issue is the voltage on your downrigger wire which is imparted by having a "hot" boat. If you take the downrigger cable out of the equation, your problem is pretty much solved.

One way to resolve the issue is switching over to the new Scotty Dyneema downrigger cable. We fished with one of Murphy's guides in Ucluelet last May and they were testing it for Scotty. Our guide seemed to like it. If you switch to Dyneema, you are guaranteed not to have voltage issues. Obviously, you can't tweak your voltage for specific types of fish, but at least you're not driving them away in droves.

That seems to be the issue to me. If your boat is "hot" and you're running steel cable then you're screwed. If you're running something that doesn't conduct electricity, then it doesn't really matter. You can't attract fish with voltage, but you won't be scaring them away either.

 

[explorer]

this is an interesting thread.
so then, if you unplug your electric downriggers when you are trolling would it solve the issue, or at least lessen the voltage?

 

[blueorca]

Explorer...Unpluging won't make any difference.
.

 

[blueorca]

Yote... I've been beside "hot" boats, but not for very long. It's surprising how many there are.

 

[marula]

Unplugging the electric downrigger has nothing to do with it. Different metals in salt water act as a battery. Electrons from on metal will flow to anouther naturally in water and the potential voltage between the metals depends on their "nobility" . The less nobility, the easier is it is for the electrons to flow off or be negative. The least nobil metal on your boat is the sacrifical zincs at 1.04 and the highest nobility is the stainless downrigger wire at .24 so you should see a natural voltage of about .8 millivolts. If you got voltage leaks or poor grounding to your electronics you will get voltage leaks (hot boat) and add to this.

The thing with a black box is you have to test all the time and keep up on the maintence of your electrical system. I keep a volt meter in the boat and constantly check the downrigger wires to battery negative.

In all reality, the impact to our smaller boats with only two lines is marginal unless your really hot, it is more important on commercial boats with lots of lines in the water.




http://www.protroll.com/blkbox8.html

 

[Tailspin]

In between the hot Bites in Sooke yesterday, LOL[xx(] I conducted some voltage tests.

With a regualar 12 pound ball i was at .62 at 69 feet on the rigger.

With a 12 pound with a stainless fin, I was at .68 at the same depth.

It should also be noted that ACDC Thunder Struck on high volume enhanced Voltage and Beverage flow as well[8D]!

I normally run between .61-.65 with 5 feet of green ganyon as snubbers for summer fish. Interesting how a wee bit of stainless on your lead can bump up voltage so much.

 

[Kisinana]

You will find that if a boat in the immediate area is running hot, it will affect the field created by your boat as well as the water salinity where you are fishing. A black box allows you to correct for any adverse conditions when you are fishing.
If you have passed by another boat and seen the ping on your depth sounder from his, this is a high frequency signal and yet you still register it because you act as collector. By the same way you can see how his boats proximity to yours can affect your electrical field.
A russian named Tesla did some interesting experiments in transmitting electricity without using wires, just rods stuck in the ground and water conducts better than earth.

 

[The Penguin]

Pure water from what I remember does not conduct its the impurities as I recall and salt water has well salt.

I think this is more important than some people realise.
Remember we are talking about MILLIVOLTS not volts so .65 milli volts is a little more than 1/2 of one thousanth of one volt. you need a decent meter to take an accutate reading. the radio shack special will not cut it.

I would sugest that all you guys whom don't think you have a problem and are catching fish that you boat falls in the zone



SAlty beaver I would gladly take your black box off your hands

 

[Kisinana]

Sorry Penguin, But we are talking Volts and millivolts are thousandths of a volt. So for chinook and coho in the Pacific Northwest we are talking 600 to 650 millivolts or 0.60 volts to
0.65 volts. True the low end cost R.S. meter will not cut it but you do not have to spend an excessive amount if this is the only thing you use it for.

 

[Riptide2]

I have real trouble buying into the black box concept. Yes, I remember testing and adjusting voltages on commercial boats when we were not catching fish. That was over 15 years ago so I can not remember the results.

Anyhow can someone explain how there can be any charge near your bait. The charge you measure at the surface will not be the same as the charge 60ft down, then you have your release clip which if you use scotty is all plastic and upto 4ft long, them you have 15 feet plus of line from the release clip. The end result has got to be 0 volts at the end of you line???

A couple of years ago I had a short in my kicker's electic start and it would shock you when you touched the handle, we were catching lots of fish with that boat before and after fixing the short.

 

[Tailspin]

I am not so convinced on the B- box theory for my needs. Adding the required zincs, with the weekly voltage test seems to work just fine and has caused me no adverse effects on getting the boat bloody. I guess it depends on your boat?

 

[saltybeaver]

Finally got the box hooked up and was up in campbell river. Had it set on .610 and hooked into two nice springs one in the boat 20lb and another to the side of the boat but got away 25-30lb nice fish . Its always the bigger one that gets away.

 

[the runt]

I also run the infamous black box.for 69bucks what the hell.Does it work yes.Can you catch fish without them yes.I also believe boats tend to catch fish mabe better than fisherman.Some guys say they can't catch a fish in their boats, here's where the box might work well, just dial it in. I had a boat about 15years ago, never boated a salmon in two yrs.got rid of it started cathing fish.I didn't have the knowledge for that back them.If you run your boat and the engine is hot, if And you think your batteries are weak and won't hardly turn over, your groung is bad. add a extra one.Don't remove your old one, leave it.

 

[hstat]

Just used the box for the first time with a glass boat. Normal voltage is .40, but had no problem boating fish as long as I was long behind the ball. Noticed that bringing fish to the net drove them nuts. Now the closer I get a fish to the boat the quieter it is, and not losing fish at the boat. So far, it is a keeper.

 

[fishin_magician]

quote:Originally posted by yammy5

Commercial trollers run 6 lines (not 50 lol) and most use a black-box system to adjust their hull voltage and line voltage. It can make a huge difference. Years ago we left the steel gill-net guard around the prop during the commercial troll season and couldn't catch a sockeye if our lives depended on it. All the boats around us were hauling them in and we couldn't get even one. We did some testing in port and the hull voltage was way too high. We had a black box the following year and it worked well but our big mistake was leaving the metal guard on the hull. Big boats can generate significant hull and line voltage but I would guess that small sport-type fishing boats don't need to worry about voltage as much, but if you have some funny wiring on your boat you could create just enough voltage ruin your odds of catching salmon. A lot of guys run a small section of rubber snubber or green marine twine off the cannon ball to help reduce current flow. Keep everything grounded. Every little bit helps!

 

[Slabby20]

What do you find the most reliable voltage setting is at Barkley Sound / Offshore / Tofino for Springs? I usually start at .055 and adjust up if nothing is happening. Thanks for your thoughts.

 

[saltspringer]

Been fishing for sixty plus years from Cow bay and the narrows to Nootka , Barkley and Port hardy and never used a black box Never had a problem catching fish as long as they were there. It seems to me that with a retention limit of two springs a day and four in possesion we're getting a little carried away with all the gadgets , maybe we're becoming a little slab happy and are becoming meat hunters!! Let's maintain a little sportsmanship and give the fish a fighting chance.

 

[scottyboy]

seems there are alot of meat hunters around , anyone ever let any big slabs go???