Specifications
Table 1: SDI Input Waveform Vertical Characteristics (cont.)
Characteristic Performance requirement Reference information
Sine-squared bars
Preshoot
SD ≤ 0.3% peak (2T5 bar)
HD
≤ 0.5% peak (2T30 bar)
Overshoot
SD ≤ 0.3% peak (2T5 bar)
HD
≤ 0.5% peak (2T30 bar)
Ringing
SD ≤ 0.8% peak-peak (2T5 bar)
Step
Response,
Typical
HD
≤ 0.8% peak-peak (2T30 bar)
Most of the error seen on the display comes
from the inherent ringing in the d igital
data. The response of the monitor is close
to the theoretical limit of a perfect sinx/x
reconstruction filter.
Blackman pulse
Baseline
Ringing
SD ≤ 0.6% peak-peak (2T5)
Pulse
Response,
Typical
HD
≤ 0.7% peak-peak (2T30)
Pulse-to-bar ratio 0.995:1 to 1.005:1 on
appropriate Sine Squared or Blackman 2T
pulse.
A sine-squared pulse near Nyquist is not
band-limited and so inherently has ringing
much larger than the waveform monitor
filter. A three term Blackman pulse with the
same HAD has much less inherent ringing,
so it is a better choice for most testing. See
Digital to Analog Conversion, Data and Filter
Requirements, SMPTE Journal Mar 1995,
Vol. 104, Fibush, Baker, Penny.
Field Rate
0.1%
Tilt, Typical
Line Rate
0.1%
Off Screen Recovery, Typical 0.1% variation in baseline of a 5 MHz
modulated pulse when positioned anywhere
on screen at any gain setting.
2 Waveform Monitors Specifications and Performance Verification
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