This makes use of a "Graduated" Panel, which holds the main path of the scale, a Shape whose Shape.geometry is a circular arc. In addition that Graduated Panel holds three different Shapes acting as templates for tick marks and a TextBlock acting as a template for tick labels.
In a Spot Panel with the Graduated Panel scale are an italic TextBlock showing the node identifier and a red elongated diamond "needle" Shape.
The needle's angle is determined by
convertValueToAngle, which finds the point on the Graduated Panel's
main path element corresponding to
data.value and computes the angle from the center to that point.
The data value is updated several times per second.
A circle Shape surrounds the Spot Panel.