Pinpoint Question

[Kelly]

What should the sensitivity of a Pinpoint 7520 be set at? I have to set mine at 40% to get rid of all the black mess on-screen. From there it seems to work O.K. but there is a solid black line showing about 2' down on-screen which is always there unless I turn the sensitivity WAY down to almost nil. I'm assuming the solid black line is prop-wash????? The transom transducer is only about 6"-8" from center of the leg of main motor. This seems to close. Also if the big motor is put down and you look at it the prop overlaps the transducer. Could this be my entire problem?????? Thanx Very much for any info.!!!!!!!!!!

[Dodge1]

I think your right about the mounting location being the problem. I have a 7520 and can take the sensitivity way up and aside from increasing the clutter on the screen, it never shows what your describing.

Call Pinpoint directly before you do anything. They are really helpfull and it's better to get it right before your transom looks like a hunk of swiss chesse.

BTW - get one of those transducer mounting plates that Cabelas sells.

Dodge

[Bruce]

I got a 7520 last year and have the same problem with the black spots on the screen unless the sensitivity is turned way down. I bought another transducer for my jonboat that I use for river fishing and the sonar unit does the same thing with that transducer on that boat too. I know people on this board are positive about Pinpoint sonar units, but so far I haven't been very impressed with the one I have. I called Pinpoint and they said to turn sensitivity down, but it doesn't seem right to have to turn sensitivity to 40% to get rid of the black spots on the screen. Bruce

[CJW]

I believe thats where every other sonar out there puts there sensitivity. Probably only at 40 % level that way there's no clutter and you probably went right over 20 fish hugging the bottom. I'd rather have the sens. so I can adjust it a whole lot higher when I'm trying to see if its a log or fish. Sounds like the first post has his transducer mounted in turbulence. Ask pinpoint. If you want a no brainer that see's only the bottom and skips alot of things buy a hummingbird. You never have to set them they don't see much anyway. Is it that tuff to hit one key then move the sensitivity down to 40? I mean it stays right there till you move it again. There's no sonar out there that does everything for you... Just my 2 cents. Craig

[jet&jig/MT]

RE: in regard to the sensitivity of the pinpoint 7520, I have one too, and I have to turn the sensitivity way down or I gey specks all over the place, when I am trolling no prop wash, but it is much worse when I am running get a lor of interference. I thought, I just didn't know how to use the unit. I am perplexed about the sensitivity setting.

[Jeff]

I just put a 7520 on my boat and don't get the total black line described above; it sounds like a motor interference thing to me. I do get a lot of clutter when I run at high sensitivity, but I think that's normal. On my two days fishing so far, I run it at about 75% sensitivity and seem to have a good picture, but to be honest, I'm not sure what all I'm seeing! Maybe it will come with a little practice. Is there a pinpoint video to give some clues on operating these units for peak performance?

[Dirk W.]

Mine does the same thing. I've sent it in 4 times and I dont believe they can fix that problem. In shallow water its a pain. I dont think its an interference thing and Ive adjusted my tranducer 10 times. On the positive side, with the sensitivity up you pick up lots of detail and the seperation is excellent. Try adjusting the max auto gain and see what that does for ya. Im interested in others opinios on this matter also.

[Hans]

The almost solid "junk" at the top of the screen is surface clutter. There are no walleyes in it.

I run my sensitivity at 60% unless I'm fishing in less than 10 feet of water, when I set it back to about 45%.

If you are bothered by 'noise' on the screen, go to the system setup menu and crank "maxautogain" back to about 6 or so. This is a much better solution than reducing gain.

Regards,

Hans

[Kelly]

Thanks alot for the input so far. I'm sure the problem lies in the transducer being far to close to the motor/prop. How far over from center would you recommend to mount it? Thanks.

[Hans]

Depends on the deadrise angle of your boat (so that it is in the water when up on plane). Actually mine is almost dead centered, just a couple inches to starboard to clear the lower unit, and it works fine. The trick is to keep in in "clean" (low-turbulence) water away from keels, clumps of rivets, or other obstructions which cause turbulence. Also, cant it just-so-slightly so it is looking slightly forward, thus keeping the bottom of the transducer fully in contact with the water at speed.

Hans

[Kelly]

Thanks Hans but my boat has rivets all along the bottom of the transom from one side to the other. Also my transducer is about 6"-8" off center to starboard and the prop overlaps the transducer by quite alot. I'm going to move it over another 6" or so, try it there and hopefully it works.

[Hans]

B4 you drill any more holes, answer this question --

When your motor is stopped (shut off) and you are just drifting, do you still have the clutter at the top of the screen?

If so, you don't have a location problem.

Hans