When using the b.b. the voltage cycles up and down between [if set for .680] .637and .685 in a matter of seconds. The riggers are electric with the positive ion feature. What do you think??

Could that be in a pulse mode? Some boxes have that feature I thought

Check your ground. You should have everything electrical grounded in one place in your boat. Preferably the negative terminal on your battery. Make sure all your connections are clean or new.

I think the Positive Ion feature is suppose to do the same thing as a Black Box. You could be doubling up.

I am with sky guy if you have a scotty black box with a digital read out. You can put it in pulse mode by turning it on then off and back on again. If you dont I would check to make sure your sleeves are staying in contact all the time with the wire. Then check your wires going to the sleeves.

Jerry,

Ditto on the rest of the responses...

However, if you're running a few electronics off the battery your box is connected to, the box may not be receiving the right power? E.g, keying the VHF mic.

Downriggin'

Thanks guys, I think we will check to make sure the spring contact is full at the dr cable. The auto stop is still connected for bringing the ball up---------- boy does that make the bb go nuts!!

My voltage was fluctuating erratically on my BB one time and I eventually tracked it down to some water inside an electrical plug. the water was intermitently making contact between the ground and hot wire. Wouldn't pop the fuse but it messed up the bb operating properly and shut the boat down completely for catching fish when using the riggers. I sure was glad to find the problem, I thought I had lost all my mojo for a while.

It sounds like your using Canon downriggers as none of the other's I know of have positive ion control. If they are Canon, I can tell you from personal experience that the BB will cause all kinds of problems. Your auto stop won't work right and neither will the BB because they're both trying to do the same thing. I quit using the BB with Canons and the problems went away.

Try this test, Jerry...

Get a digital multimeter.
Disconnect your black box from your rigger cables, to eliminate this variable.
Go out, away from the marina and other boats, and lower your downriggers to where you normally fish (say 60ft).
Set your multimeter to DC, then touch the black probe from your meter to the negative post on your battery, and touch the red probe to your downrigger wire... measure the voltage... this is your boat's "natural" voltage. Hopefully it's in the range of 0.5v+ to 1.0v+. (If it isn't, you have other problems, and either need to add zincs to your boat or you need to trace down an electrical leak on your boat, like a broken wire or a bildge pump or something leaking voltage.)
Now keep holding the probes there (one to the battery and one to the rigger cable), and have someone push the button to bring the downrigger up.
My guess is that your voltage will skyrocket, to 7.0v+ or so...

I've never done this test myself, but I've heard that the Cannons induce a high positive voltage on the line while retrieving the downrigger ball... these riggers have an internal circuit that is similar to a ground fault circuit, when the ball breaks the surface of the water, the downrigger senses that, and stops retrieving.
I'm guessing what is happening is that your black box is sensing this change in voltage and is trying to override the high voltage and regulate it back down to the "induced voltage" setting that you've set it to.
Obviously, if your downrgger cable voltage ever goes above 1.0v+, you're turning away fish... 7.0v+ is really hot, really bad...

If this high voltage isn't happening when you're retireving your downrigger balls, leave your downrigger ball in the water, keep holding the probes where they are, (black to battery neg post and red to rigger cable) and then have someone turn your electronics on and off, key the VHF mic, etc... look for any big changes in voltage... you might have some other electrical problem on your boat, like a weak or corroded ground wire somewhere...

But, I've heard of this Cannon problem before, and I've talked to guys that have had both electric Cannon's and electric Scotty's on the same boat, and the Scotty's caught way more fish, and it's my theory is that this high voltage on the Cannons is the reason. The Scotty electrics use a mechanical method of sensing when they should stop retrieving... you put a plastic stop on your downrigger line, and when it comes up, the rigger senses the stop and stops there...

Long story short, it's time to trade those Cannons in for a pair of Scotty's... (or just get one Scotty for now and see if it catches more fish than the Cannon)

-N.

Stormin
I don't have a lot of experience with all this, as many know I have only owned downriggers for a few weeks
Mine had homemade black boxes/ion control on them that were external and did excactly what you are talking about Stormin but the voltage on the cable was closer to 12v and the darn things were wired into the motor circuit on the 'rigger so the only time the whole contraption would work was while the 'rigger was going up/down. I disabled and removed the home made stuff after talking to the service guys at canon (very helpful, even faxed me wiring schematics ) and he was flat out alarmed that there was any voltage fluctuation more than .1 v or so at the cable at all.
I have not had an opportunity to measure the voltage on mine in salt at all yet, or any other tests that you mentiond yet. Nor have I fished with any other downrigger in my life, so I am likely the least qualified person here to ask any question at all or come to any hard conclusions, it just would seem to me that since Jerry is basically running two black boxes on the same 'rigger wire( positive ion control and a black box) they are competeing with one another espescialy since the voltage fluctuation is so low ( several hundreths of a volt not 7 to 9 volts. In addition to all the recomended tests Stormin mentioned check out this link if you haven't yet. They have posted their guide on the net for all to read and it goes even deeper into depth on the troubleshooting Stormin was talking about http://www.protroll.com/blkbox.html
Taking all of the above into account it would seem logical to try using each unit without the other and see what the voltage is. The only problem might be in turning off the P.I.C. at the 'rigger but I would think if you unplugged it at the power source Jerry, and killed all power to the rigger except what the BB is doing you might come up with a nice steady voltage. I agree with Easy and am very curios as to why you do not use the factory P.I.C. on the 'rigger to get the voltage where you want it? I am not trying to seem like a know it all, I have no experience with the P.I.C. from canon( or anything else concerning downriggers) And I definitly do not want to second guess storminN I am just trying to follow a logical train of thought here and help out... Of course I am probably a day late and a $ short and you have already got it fingered out...