Table of Contents
Advertisement
Oscilloscope displays
What you see on the oscilloscope while adjusting the MVP 104GX to match the
genlock signal depends on the type of signal used, the type of oscilloscope, and the
procedure the scope requires. This section shows some examples of oscilloscope
displays.
Figure 2-6 below shows the genlock input signal (top) and an out-of-alignment
NTSC composite sync output signal (bottom) displayed on a waveform monitor to
check for alignment. When the phases are aligned, the wave peaks on the bottom
waveform should line up with those in the reference signal above it.
With this method there is no way to know if the signals are 180º out of phase. A
delayed sweep on a time-based scope would allow a more accurate display of the
input and output signal phase relationships.
Figure 2-6 — Superimposed waveforms
A vectorscope is more accurate than a waveform monitor. Figure 2-7 shows an
example of a vectorscope display when the horizontal phase is adjusted to align it
with the burst (genlock) vector. Adjust the horizontal phase by rotating the encoder
knob until the difference between the two vectors is 0º. This example shows black
burst only (with no color). The burst vector is pointing to the left from the center.
300
290
280
270
260
250
240
Figure 2-7 — Vectorscope screen during horizontal
phase adjustment
0
10
350
340
20
30
330
40
320
50
310
120
230
130
220
140
210
150
200
160
190
170
180
60
70
80
90
100
110
MVP 104GX Installation
2-9
Advertisement
Table of Contents
