Interference with my electronics

[Chris Hoffman]

I was wondering if anyone can give me some pointers on trying to fix / locate the issue of interference.   I have a MK Fortrex 101 36v with built in US2 transducer.  I have the HB 788ci HD connected to the US2 2d sonar transducer in the Fortrex.  When I engage the TM I get severe interference.  I have a HB 898 ci SI also located at the bow, but it is connected to a side imaging transducer that is hooked externally to the TM.  Both units are connected to the Ethernet hub.  While running the TM, I don't experience interference on the HB 898. 

I have attempted to trouble shoot by attaching the 788 cables directly to the 898 and I still got interference when engaging the TM.  I removed the power cable to the 788 and splice direct to a battery hoping to eliminate the battery connection.  I still received interference.   Next I thought could it be the Ethernet hubs, removed the 788 from the network and still interference.  The only places that I have not checked is the foot control and the head unit.  I am told that there is a fuse located underneath the foot control as well as in the head unit of the fortrex. 

Any help is greatly appreciated.

[Don C]

Chris before you rip the head  apart try take a piece of wire run it from the ground wire on your MK in the front of your boat down to the top of the MK head  scratch a spot on top of the head put the wire on the clean spot put a clamp to hold the wire    I had a lot of big black lines  with the ground wire all gone  I put it under the clamp that holds the transducer 

[Chris Hoffman]

Thanks for the tip Don,  I will give that a try, but  what are you referring to by taking a piece of wire run it from the ground wire on your MK in the front of your boat ??  HB is sending me a new power cable with a choke that has a ferris built inside to help eliminate RF interference. 

[Don C]

Chris you take a piece of wire 6 feet long
under the front of your boat find the big wire that is the ground for your TM hook the wire to it run the wire along your TM down to the head were the prop is scratch a small spot to bare metal on top of the TM motor head put the bare part of the wire on the part you scratch off put a clamp to hold wire to the bare spot
WHAT YOU ARE DOING IS GROUNDING THE HEAD OF THE TM

[ratherbfishin]

Chris,

Don is probably right. His fix is well worth trying.
I was having a similar issue with my Lowrance HDS at the end of the season when running my MK.  I'm going to run a thin insulator:
either a piece of rubber or some guys recommend a piece of lead sheathing between the transducer and TM (I don't have a built in transducer)

If Don's fix doesn't work, try going on to bassboat central (link off the NHbasshunters link page) and chances are somebody else
has had a similar issue.

Just curious, how is your sensitivity set on your 788 compared to your 898?

Good luck,
Andy