Environnement Envea MIR 9000, Техническое руководство, Страница: 132 / 212

Environnement
S.A
MIR 9000
Duplication prohibited
5–14
JULY 2009
5.2.6.2 Adjustment of the sampling
Use the two measurement channels of the oscilloscope.
Connect the probe of channel 1 to Pt 17 to visualize the signals and the probe 2 to Pt 19 to visualize
the sampling.
This should be centered on the high levels. Never perform any sampling on the high-to-low or low-to-
high transitions of the signal.
The adjustment will be made with the aid of the positioning of the optical forks.
After releasing the two screws holding it in place, remove the "optical forks” assembly until the
sampling is centered on the high levels.
Refasten the two screws supporting the optical forks.
INCORRECT
Samples made too far to the left of the high level and overstepping on the low-to-high transition: that
type of adjustment makes the measurements much noisier.
Figure 5–2 – Sampling Oscillogram # 1
INCORRECT
Samples made too far to the right of the high level and overstepping on the high-to-low transition: that
type of adjustment makes the measurements much noisier.
Figure 5–3 – Sampling Oscillogram # 2