Steve wrote:
Hay all! After having this nice truck for 9 years now,
im finally going hf mobile! Have Icom 730 rig, mounted
in 96 Ford F-350 powerstroke 7.3 Liter ?Diesel truck,
1ST- Mega noise on ignition system! NB doesnt help at
all. No matter what speed you drive it gets worse at
highway speeds, *Antenna here is a Henry Allen TX bug

I have a 1995 Ford Explorer. Using an IC-706MKII and a Webster
Bandspanner antenna. I realize your vehicle is diesel and mine is gas,
but the solution may be the same. My problem stemmed from the fuel
pump. Ford has a retrofit electrical filter for the fuel pump. Noise
went from an S-8 to S-0.



2nd- Biggest problem, is when you key the mic even not
modulating it, just keying it, slows the motor down
like you take your foot of the accellerator and applying the
brakes. This happens regardless what power I have the
icom set at! 50 watts, 30 watts, same thing! ***
I have tapped in the power fuse box thats under the dash,
for direct power to rig, would directly having it go to
the batteries up front help any? Or is this little rf
messing with the computer module under the hood next to the
firewall? Back in January I had the right side power
harness replaced, like the set of sparkplug wires that
go to the individual injectors on the right side of the
motor. Could there be a ground not connected from the
repair shop? Truck has 142K mileage, runs like clock,
but im affraid of the excessive rf power messing with that
computer module?

RF feedback into the computer is a valid concern. I would recommed a
direct connection to the vehicle battery. This is generally the
recommended method of connection for high current applications anyway.

What sort of feedline do have you going from the rig to the antenna?
I would probably go with RG8X. Have you checked the condition of the
UHF connector on your coax where it connects to the rig? Make certain it
has GOOD contact with the shield portion. How is the coax terminated at
the antenna? Is truck bed solidly bonded to the chassis frame?

You may try re-routing the coax cable to the opposite side of the vehicle.

It is possible a floating ground on the replacement wiring could be
causing your trouble. You mentioned "sparkplug" wires...which I doubt
you have.

Do these problems show up on ALL HF bands?