[RFI] Ferrite Beads

[Ford Peterson]

Tom wrote:

...SNIP...

> Sometimes finding a sweet spot for grounding helps. There
> isn't a single bead in my truck wiring. Just grounding two
> points cured it all.
> 
> 73 Tom

I have studied your website about the powerstroke story extensively.  I appreciate having those pages available as a resource.  I have spent hours trying to deaden the radiated noise using grounding straps.  The problem is traced back to the cops.  Toyota went through a bunch of effort to ground various components already.  I can see their straps and have jumpered every one of them and added more of my own.  No improvement!  

The harness leading to the COPs is a buzz of noise.  It all starts with each COP and the noise adds all along the length of the harness back to the engine controller.  It is the most intense at the COPs.  

Getting help from Toyota is useless in this effort.  They do not sell vehicles into the public service market and therefore could care less about 2-way radio noise.  They suggest I use a Cell phone instead!  Their measure of performance is whether you can hear the noise on the AM radio when a station is tuned in.  Well, you can hear the ignition noise between stations and on weak stations, but if the AM station has any field strength at all, the S/N is good enough to swamp out the COP noise.  It's S7 to S9 on my 706MKIIG.  The noise blanker is very effective, but the resulting distortion tells me that the noise is taking its toll...  I want to fix this once and for all.  I managed to get rid of the fuel pump noise problems by moving the antenna to the rear stake pocket.  But the COPs can be heard from another nearby vehicle and nothing when the antenna resonator is removed.  It's radiated noise.

Since there is no connector set available from Toyota, I'm stuck either slashing the harness and inserting a toroid with 4 conductors and cobble together some kludge job that would void the warranty, or use a single toroid (or set of toroids) slipped over the wires right at the COP.  I've got a couple inches of wire to play with, that's it!

Thanks for the help guys.  What hair was left on my head is mostly scattered around the room on the floor.  I'm hopeful that the choke can be made effective enough to make the investment worth while.

Ford-N0FP
ford at cmgate.com