User's Manual
Vave Personal Ultrasound • USER MANUAL
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CONFIDENTIAL & PROPRIETARY. CAUTION — Investigational device. Limited by Federal law to investigational use. Not commercially available in the US.
Electromagnetic Interference
The way an electromagnetic interference (EMI) from other equipment aects the Vave Personal Ultrasound depends
on the system’s operation mode, image control settings, and the type and level of electromagnetic phenomena.
Electromagnetic phenomena may be intermittent, making it dicult to identify the source.
If you experience EMI, use caution if you continue using the system, or consider relocating your system.
The following table describes typical interferences seen in imaging systems. It is impossible to describe all
manifestations of interference, because it depends on many parameters of the transmitting equipment.
Some factors include the type of modulation used by the signal carrier, the source type, and the transmitted level.
It is also possible for the interference to degrade the imaging system’s performance and become invisible on the
image. If the diagnostic results are suspicious, confirm the diagnosis using other methods.
Imaging Mode ESD1 RF2 Power Line3
B-mode Change of operating
mode, system settings
or system reset. Brief
flashes in the displayed
or recorded image.
For sector imaging scanners, white
radial bands or flashes in the center
lines of the image. For linear imaging
scanners, white vertical bands,
sometimes more pronounced on the
sides of the image.
White dots, dashes or
diagonal lines ner the
center of the image.
Possible causes of electrostatic interference:
• ESD caused by charge buildup on insulated surfaces or persons.
• RF energy from portable phones, hand-held radios, smart devices, commercial radio and TV stations.
• Conducted interference on power lines, switching power supplies, electrical controls and lightning.
Separation Distance
Recommended Separation Distance
The following table shows recommended separation distances between the system and any RF-transmitting
equipment. To reduce the risk of interference, when using portable and mobile RF communications equipment,
follow the recommended separation distance (calculated from the equation applicable to the frequency of the
transmitter). Ensure that field strengths from fixed RF transmitters, as determined by an electromagnetic site survey,
are less than the compliance level in each frequency range as noted in the table.
Field strength is dicult to predict with accuracy if it comes from fixed transmitters, such as base stations for
radio (cellular/cordless) telephones and land mobile radios, amateur radio, AM and FM radio broadcast, and
TV broadcast. To assess the electromagnetic environment from fixed RF transmitters, consider conducting an
electromagnetic site survey. If the measured field strength in the location in which the system is used exceeds
the applicable RF compliance level in the table, observe the system to verify normal operation. If abnormal
performance is observed, apply additional measures, such as reorienting or relocating the system.
At 80 MHz and 800 MHz, the higher frequency range applies.
The recommended separation distance guidelines in the following table may not apply to all situations.
Electromagnetic propagation is aected by absorption and reflection from structures, objects, and people.
The table here provides guidance on conducted and radiated interference from portable and fixed RF
transmitting equipment.