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 2-6below 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 2-7shows 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.

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Figure 2-7 — Vectorscope screen during horizontal phase adjustment

MVP 104GX Installation

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Image 17
Extron electronic MVP 104GX manual Oscilloscope displays, Superimposed waveforms