GE Venue 50 Basic Service Manual page 61

EMI prevention/abatement
EMI RULE
Be aware of Radio
Frequency sources
Ground the
Ultrasound system
Replace all screws,
Radio Frequency
gaskets, covers,
cores
Replace broken
Radio Frequency
gaskets
Do not place labels
where Radio
Frequency gaskets
touch metal
Use GE specified
harnesses and
peripherals
Take care with
cellular phones
Properly route
peripheral cables
Venue 50 – Basic Service Manual
5447566-100 English Rev. 7
Table 2-6: EMI prevention/abatement
• 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.
Poor grounding is the most likely reason an Ultrasound system will have noisy
images. Check grounding of the power cord and power outlet.
• 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.
If more than 20% or a pair of the fingers on an Radio Frequency gasket are
broken, replace the gasket. Do not turn on the Ultrasound system until any loose
metallic part is removed.
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.
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.
Cellular phones may transmit a 5 V/m signal; that could cause image artifacts.
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.
General Requirements
DETAILS
2-9