[Mobile-Portable] Noise in new Ford 6 liter Turbo diesel ?

[K7fe at aol.com]

Try this source for ferrite:
 
_http://www.allelectronics.com/cgi-bin/category.cgi?category=235&type=store_ 
(http://www.allelectronics.com/cgi-bin/category.cgi?category=235&type=store) 
 
Be sure that your exhaust pipes are well grounded.
They can generate electrical noise by rubbing against other metal parts and  
wind moving over the pipe may generate static electricity or they may just  
re-radiate noise generated somewhere else.
 
An exhaust pipe is bolted to the engine at the exhaust manifold. Many  
vehicles hold the long exhaust pipe up, in several places, with  insulated/flexible 
straps to reduce mechanical vibration and audible noise. Lets  call these 
straps "insulators." The length of the exhaust pipe becomes an  antenna, 
collecting and re-radiating your ignition spark and other noise to your  transceiver 
antenna like a "passive repeater." The longer the length of  insulated exhaust 
pipe, the better radiator. (remember "Bigger is Better" for  antenna's). By 
attaching shorting straps from the exhaust pipe to ground (frame)  in several 
places along the length and end, you lower the impedance and thus  reduce the 
ability of the pipe (antenna) to radiate.
 
You might ask, isn't the exhaust pipe at DC ground? Yes, it is, but so are  
both sides of many antenna's like a Folded Dipole, Quad, Triangle, Halo, most  
Screwdrivers and so on. So it appears that DC ground and RF ground are 
different  animals and must be analyzed accordingly. "Do not rely upon ohm meter 
reading to  determine RF grounds!" 
 
Every large chunk of conductive material on your vehicle needs to be tied  
electrically to the other metallic parts (in more than one place), with strap or 
 braid. Example: Hood to fender, fender to frame, frame to engine, frame to  
exhaust, frame to body, trunk to body, A/C lines to frame, etc. Strap is 
better  in that it has a lower RF impedance than braid and should be used where the 
 flexibility of braid is not required. Some vehicle manufacture's do a good 
job  of tying their parts together electrically, others do not. Ford has always 
been  weak in this area. 
 
The microprocessors are also a source of noise, (my Windstar has five,  which 
snap on ferrite suppressed), as is the headlight control  module.  My vehicle 
has two, one for the headlights and one in the rear for  the tail lights and 
they both generate a buzzing noise when the lights are  on.  Control wires run 
from the switch on my dash to each light  module.  I am still working on 
solving that noise.  The A/C fan motors  needed a .5 to a .05ufd across the leads. 
 Remember that a capacitor to  ground may be more effective at providing a 
low impedance path to ground for RFI  than ferrite, especially since we often 
only have one turn of the wire passing  thru the ferrite.  Use more turns thru 
the ferrite if you can or multiple  ferrites on a wire.  A combination of both 
ferrite and capacitors may be  required, since not all electronic modules may 
like a capacitor to ground on  every lead out of the module.  You can use an 
oscilloscope to look  for RFI noise sources in your vehicle and filter those 
spots  first. 
 
My Mobil station is described in more detail on my QRZ.COM bio.
 
I hope this helps.
 
73,
Terry, K7FE