Thread: 997 woes.........

Originally Posted by jaxsprat

To bigfish 5, & canepole On the sidefinder site when many folks were complaining of interference from trolling motors the first fix they always recommend is running a separate ground wire from troller back to battery seems it has worked for most. Just know what I read, not to kean on electronic stuff

Electronics has its own separate battery. Not on engine start battery or trolling motor battery. I believe the noise comes from the cable routing.

Could you wrap the transducer and power cables for the 997 that run parallel to the other power wires separately in aluminum foil and ground them?

I ran the transducer cable in the same channel as the other power cables running from the transom to the console and do not have any problems. When running both the Lowrance and 997 at the same time, I get a small amount of interference on the Lowrance and no interference on the 997.

Originally Posted by PanMan_VA

Could you wrap the transducer and power cables for the 997 that run parallel to the other power wires separately in aluminum foil and ground them?

I ran the transducer cable in the same channel as the other power cables running from the transom to the console and do not have any problems. When running both the Lowrance and 997 at the same time, I get a small amount of interference on the Lowrance and no interference on the 997.

I use to have about 100' of 16 gauge audio cable made that way. We used it for wiring speakers for paging systems attached to our phone system. Made great power cabe.

Cane Pole,

Can you take a snapshot of this and email it to me directly. My email addres is [email protected]. I would like to see this.

One question are you running both the Garmin 240 and the 997 at the same time.

Originally Posted by Joby @ Humminbird

Cane Pole,

Can you take a snapshot of this and email it to me directly. My email addres is [email protected]. I would like to see this.

One question are you running both the Garmin 240 and the 997 at the same time.

Yep. The Garmin and 997 on at the same time. Only occurs when side scanning. Odd, since such difference in frequencies. Cut Garmin off, SI clears.

Be couple of weeks before we go back to lake. I will try to remember. Remembering things isn't one of my stronger points anymore. But I will definitely try.

Canepole : Been 40 some years for me since my electronics schooling. Seems to me I rmember something about " harmonic frequencies ". Whereas 60hz would be a harmonic of 360hz 120hz 600 hz . Noise is usually displayed in an electronic circuit as " snow ".
Noise is normally overamplification of a transient signal that causes the intrinsic design of said circuit to malfunction.

Early TVs had a noise filter circuit in them to supress transient induced voltages or redirect them to ground. Try some sort of shielding between the Garmin wires and the Humminbird. Ground shielding at both ends.

Moral of story : Engineers may design a circuit but it takes a tech to make her work.