Had a major computer crash here last week. Somebody responded to my plea
for help concerning noise in an F-150 that is killing my FT-857's HF
ability. I lost everything since I had to reformat the hard drive and start
over again.

Someone pointed me to a website that had a Technical Service Bulletin for
fuel pump RFI. I'd like to get that again to print out. It doesn't appear
that it (fuel pump) is an issue in my truck, but if there is a TSB for the
noise, I'd like to make them do it under warranty. All I got today was
"Good Luck!" from the Ford dealer. I took a book on RFI to show them
possible causes and the guy kept saying the 2003 doesn't have spark plug
wires so that can't be the source. Then I said it has a coil and they said,
nope, each spark plug has its own coil attached right to the top of the
plug. I concur, but there is a coil (in fact, 8 of them) and as long as
there is, it must be generating high voltage to fire the plug, therefore,
there is a primary circuit that tells the coil to fire. My contention is
that any RFI generated by the spark plugs could be radiated back out of the
coil through the primary circuit. The tech disagreed by stating that there
is no primary circuit, that the coils are controlled by the computer
directly. Duh. There is a wire connected from the coils to the computer.
Sounds like an antenna to me. First thing they said was that my (cheap)
radio doesn't have enough filtering on the DC power line. Bull****! When
the truck is off, it's quiet as a mouse. Start the truck and the noise
starts. Popping goes up and down with engine speed. Noise blanker helps
cut noise from S9 to S3, but I want better than that! If I disconnect the
antenna from the radio with the truck running, noise goes to zero. So, you
tell me that the noise is coming in through the DC power leads.

I asked if there was anybody I could contact direct at Ford...Nope. I guess
Ford has no employees or engineers in Detroit. Model company...no wonder
they can give away trucks...NO OVERHEAD!! Ya, right...

****ed in Wisconsin,

Scott N0EDV


--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

Scott wrote:

Had a major computer crash here last week. Somebody responded to my plea
for help concerning noise in an F-150 that is killing my FT-857's HF
ability. I lost everything since I had to reformat the hard drive and start
over again.

Someone pointed me to a website that had a Technical Service Bulletin for
fuel pump RFI. I'd like to get that again to print out. It doesn't appear
that it (fuel pump) is an issue in my truck, but if there is a TSB for the
noise, I'd like to make them do it under warranty. All I got today was
"Good Luck!" from the Ford dealer. I took a book on RFI to show them
possible causes and the guy kept saying the 2003 doesn't have spark plug
wires so that can't be the source. Then I said it has a coil and they said,
nope, each spark plug has its own coil attached right to the top of the
plug. I concur, but there is a coil (in fact, 8 of them) and as long as
there is, it must be generating high voltage to fire the plug, therefore,
there is a primary circuit that tells the coil to fire. My contention is
that any RFI generated by the spark plugs could be radiated back out of the
coil through the primary circuit. The tech disagreed by stating that there
is no primary circuit, that the coils are controlled by the computer
directly. Duh. There is a wire connected from the coils to the computer.
Sounds like an antenna to me. First thing they said was that my (cheap)
radio doesn't have enough filtering on the DC power line. Bull****! When
the truck is off, it's quiet as a mouse. Start the truck and the noise
starts. Popping goes up and down with engine speed. Noise blanker helps
cut noise from S9 to S3, but I want better than that! If I disconnect the
antenna from the radio with the truck running, noise goes to zero. So, you
tell me that the noise is coming in through the DC power leads.

I asked if there was anybody I could contact direct at Ford...Nope. I guess
Ford has no employees or engineers in Detroit. Model company...no wonder
they can give away trucks...NO OVERHEAD!! Ya, right...

****ed in Wisconsin,

Scott N0EDV

--
Scott
http://corbenflyer.tripod.com/
Building RV-4
Gotta Fly or Gonna Die

You can check the Google archive for this newsgroup at:
http://groups.google.com/groups?hl=e...ateur.homebrew

--
We now return you to our normally scheduled programming.

Michael A. Terrell
Central Florida

On Fri, 30 Jan 2004 23:16:19 -0000 "Scott"
wrote:

If I disconnect the
antenna from the radio with the truck running, noise goes to zero. So, you
tell me that the noise is coming in through the DC power leads.

Disconnect the antenna wire and verify that it's shield is still well
grounded. The antenna end of the antenna wire must be well grounded to
the body AT THE ANTENNA end to minimize noise pickup.

Lots of times this connection is poor, either because of corrosion or
paint between the antenna body and the car body, or corrosion between
the antenna body and the coaxial shield. Either way it's a major
source of noise pickup.

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
-----------------------------------------------

On 30 Jan 2004, "Scott" wrote in
:

Had a major computer crash here last week. Somebody responded to
my plea for help concerning noise in an F-150 that is killing my
FT-857's HF ability. I lost everything since I had to reformat the
hard drive and start over again.

Someone pointed me to a website that had a Technical Service
Bulletin for fuel pump RFI.

I believe this is the site you're looking for:

http://www.arrl.org/tis/info/pdf/W1MG.pdf

Unfortunately that article is dated 2002, so your vehicle wouldn't be
covered.

You may want to try the following information:

Ford Motor Co
300 Renaissance Center
PO Box 43360
Detroit, MI 48243
USA

Tel: 800-392-3673 (all makes)
800-241-3673 (towing and dealer location service)
800-232-5952 (TDD)

Also from the original thread:

Tell the dealer to look up Ford's technical service bulletin
TSB 93-15-6 and/or TSB 95-11-3 (I believe the latter is an updated
version of the former). This describes the problem, identifies the
Ford filter part which is to be installed inside the fuel tank on the
pump wiring, and describes the procedure.

One last bit of information for you that I found online:

I recently installed an Icom 706 in a Ford (2002) F-150 pickup with
a 4.6 L. V-8. It has the Coil on Plug ignition system.

There is very heavy ignition noise (clearly "classic" ignition noise
- NOT fuel-pump noise). It is s-9 on 80 and 20 mtrs - less on other
frequencies.

This is my first entry into HF mobile since HW-12's in the 60's. I
have tried wiggling wiring, grounding the hood and other components,
disconnecting some cables, etc. - No luck.

I really don't understand this coil-on-plug technology, but I have
been told there are no resistor-plugs and of course no resistor
wires.

Any suggestions as to how to proceed would be most appreciated! I
have tried unplugging wiring to each plug one-at-a-time with no
difference noted in the interferrence level. What else could I do
to further diagnose the precise cause/source of the interferrence?

Could I expect to get any help from Ford?

My latest Mobile Handbook is from the 60's - out of date to say the
least. Does the latest Mobile Handbook edition have any information
on modern-technology ignition systems? My 2003 ARRL Handbook (the
"general" Handbook) has a paragraph - not at all helpful.

All of the RFI is through the antenna - when I disconnect the
antenna from the mount, all RFI disappears. I can hear it on my
fixed station when the vehicle is in the driveway.

I'm a happy Ford truck owner as well. They are noisey beast.
You'll have to bond all the sheet metal to the frame rail, not just
the hood. You'll also have to run a bonding strap from the negative
of the battery to the frame rail. Ford make one good connection
from the battery to the engine block but the chassic and the engine
are both on rubber
grommetts. Use your frame rail as your ground buss. Run bonding
straps from the rail to all the fenders, etc. Measure the
resistance across the door hinges. If the resistance is over 2
ohms, install a shunt across the hindge. Bond the tail pipe to the
frame rail at three points, the tail pipe, between the resonator
and the muffle and between the muffle and the cataletic converter.

Also, the brake sensors produce a lot of noise. Make your test
while parked or you'll just add another noise component to the mix.

Your power leads from the radio should be going directly to the
battery.
So, as not to void my warrantee I installed a second battery inthe
truck bed and use it as dedicated power for the transceiver. Your
coax from the antenna should be bonded to the frame rail as close
to the base of the antenna as possible. Installation of an antenna
isolator would help eliminate any common mode noise that might be
pickedup by the coax.

Hope all this helps

73
kd7qxu