  The article proves first that the constant quality factor (Q) contours for
passive circuits, while represented on a 2D Smith chart, form circle arcs on a
coaxal circle family. Furthermore, these circle arcs represent semi-circles
families in the north hemisphere while represented on a 3D Smith chart. On the
contrary we show that the constant Q contours for active circuits with negative
resistance form complementary circle arcs on the same family of coaxal circles
in the exterior of the 2D Smith chart. Also, we find out that these constant Q
contours represent complementary semi-circles in the south hemisphere while
represented on the 3D Smith chart for negative resistance circuits. The
constant Q - computer aided design (CAD) implementation of the Q semi-circles
on the 3D Smith chart is then successfully used to evaluate the quality factor
variations of newly fabricated Vanadium dioxide inductors first, directly from
their reflection coefficient, as the temperature is increased from room
temperature to 50 degrees Celsius ({\deg}C). Thus, a direct multi-parameter
frequency dependent analysis is proposed including Q, inductance and reflection
coefficient for inductors. Then, quality factor direct analysis is used for two
tunnel diode small signal equivalent circuits analysis, allowing for the first
time the Q and input impedance direct analysis on Smith chart representation of
a circuit, including negative resistance
