General Ultrasound system requirements
Ultrasound System – Common Service Information 3-19
Direction 5444964-100 English Rev. 5
EMI prevention/abatement
Prevention/abatement details are provided below: 
Table 3-17:  EMI prevention/abatement
EMI RULE DETAILS
Be aware of Radio 
Frequency sources
• Keep the Ultrasound system at least 5 meters (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 Ultrasound 
system
Poor grounding is the most likely reason an Ultrasound system will have 
noisy images. Check grounding of the power cord and power outlet.
Replace all screws, Radio 
Frequency gaskets, 
covers, cores
• After you finish repairing or updating the Ultrasound system, replace all 
covers and tighten all screws.
• Any cable with an external connection requires a magnet wrap at each end.
• Install all covers. Loose or missing covers or Radio Frequency gaskets 
allow radio frequencies to interfere with the ultrasound signals.
Replace broken Radio 
Frequency gaskets
If more than 20% or a pair of the fingers on a Radio Frequency gasket are 
broken, replace the gasket. Do not turn on the Ultrasound system until any 
loose metallic part is removed.
Do not place labels where 
Radio Frequency gaskets 
touch metal
Where applicable, never place a label where Radio Frequency gaskets meet 
the Ultrasound system. Otherwise, the gap created will permit Radio 
Frequency 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 route peripheral 
cables
Where applicable, 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.