Thought Technology Ltd. Procomp Infiniti, Руководство по оборудованию

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Measurement Unit
The MyoScan-Pro sensor’s active range is from 20 to 500 Hz. It
can record SEMG signals of up to 1600 microvolts (
μ V), RMS.
On the back of the sensor, there is a small switch with three
positions: 400N, 1600W and 400W. In the 400W (wide
bandwidth) position, the sensor will be sensitive to the full 20-
500Hz bandwidth. When recording SEMG from the upper body
muscles, the sensor might pick up some electrical interference
from the heart muscle, which is usually seen as a sharp spike
occurring at every heartbeat. This noise can be filtered out by
moving the switch to the 400N (narrow bandwidth) position. In
this position, the sensor will only be sensitive to frequencies
between 100 and 200 Hz. The third position, 1600W is for
monitoring large muscle groups like thigh muscles. At the
400W or 400N positions, the sensor’s amplitude scale is 400
μ V, which allows for a good resolution for most of the body’s
muscles. The larger body muscles can produce microvolt
readings of up-to 1600
μ V. To properly monitor their activity,
set the sensor to the 1600W position.
The MyoScan sensor’s active range is from 10 to 500 Hz. It
can record SEMG signals from zero up to 2000 microvolts (
μ V).
Sensor Placement
When placing an SEMG sensor on a muscle site, the best
readings are obtained when the sensor is placed on the muscle
belly and its positive and negative electrodes are parallel to the
muscle fibers. When using the extender cable, though, the
direction of the fibers becomes irrelevant since the electrodes
are frequently placed on different muscle groups. The positive
and negative electrodes should still be placed on the muscle
bellies. The reference electrode is best placed on a relatively
neutral site, like a bony prominence, preferably at an equal
distance from the other two electrodes.
Typical Signal
The typical waveform of an RMS SEMG signal is shown below:
Changes in amplitude are directly proportional to the muscle's activity. Normal resting values are
usually around 3 to 5
μ V (they can be as low as .3 or even less for a profoundly relaxed muscle).
ProComp Infiniti Hardware Manual 23