GE M
EDICAL
S
YSTEMS
D
IRECTION
FC091194, R
EVISION
02
V
IVID
7 / V
IVID
7 PRO S
ERVICE
M
ANUAL
Chapter 2 - Pre-Installation
2 - 5
2-2-3 EMI Limitations (cont’d).
Table 2-5
EMI Prevention/abatement
EMI Rule
Details
Be aware of RF sources
Keep the unit at least 5 meters or 15 feet away from other EMI sources. Special shielding may
be required to eliminate interference problems caused by high frequency, high powered radio
or video broadcast signals.
Ground the unit
Poor grounding is the most likely reason a unit will have noisy images. Check grounding of the
power cord and power outlet.
Replace all screws, RF
gaskets, covers, cores
After you finish repairing or updating the system, replace all covers and tighten all screws. Any
cable with an external connection requires a magnet wrap at each end. Install the Card Rack
cover over the Card Rack. Loose or missing covers or RF gaskets allow radio frequencies to
interfere with the ultrasound signals.
Replace broken RF
gaskets
If more than 20% or a pair of the fingers on an RF gasket are broken, replace the gasket. Do
not turn on the unit until any loose metallic part is removed.
Do not place labels where
RF gaskets touch metal
Never place a label where RF gaskets meet the unit. Otherwise, the gap created will permit
RF leakage. Or, if a label has been found in such a position, move the label.
Use GE specified
harnesses and peripherals
The interconnect cables are grounded and require ferrite beads and other shielding. Also,
cable length, material, and routing are all important; do not change from what is specified.
Take care with cellular
phones
Cellular phones may transmit a 5 V/m signal; that could cause image artifacts.
Properly dress peripheral
cables
Do not allow cables to lie across the top of the Card Rack or hang out of the peripheral bays.
Loop the excess length for peripheral cables inside the peripheral bays. Attach the monitor
cables to the frame.
