Tektronix 1730 Series, Инструкция по эксплуатации

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1730–Series Operating Instructions
2–23
HAD that exceeds 18
m
s, simply measure the bar top in increments by position-
ing the bar to the left or right from the leading or trailing edge. Note that when
the leading or trailing edge is on the appropriate arrow, the first or last 1
m
s is
automatically excluded from the measurement.)
Pulse–to–bar K–Factor measurements are made using the solid and short dashed
lines to the left of the line time distortion structure. These lines are scaled
according to the following formulas:
1 and 1
(1–4K) (1+4K)
Where: K=0.02 for 2% K–Factor (dashed lines)
K=0.04 for 4% K–Factor (dashed lines)
Calibrated 5X Gain increases resolution to 0.4% and 0.8%.
This scaling is described in detail in CCIR Standard Volume 5, 1966.
Make sure that the center of the bar is at 100 IRE when blanking level is at
0 IRE (use VAR to adjust gain, if necessary). If necessary, use the HORIZON-
TAL Position control to place the 2T pulse over the measurement area and
measure its amplitude.
The Horizontal reference line is the baseline at 0 IRE (NTSC and PAL–M) or
0.3 V (PAL). This timing line is 12 divisions long on NTSC graticules (12.4
divisions for PAL), and takes on different timing intervals depending on the
sweep rate selected. In 2 line sweep each major division is 10
m
s, and when
magnified (X10), each major division equals 1
m
s. In 1 line sweep each major
division is equal to 5
m
s, and when magnified (X25) each major division equals
0.2
m
s. In 2 field sweep the timing scale is of no real value, since this is a
monitoring mode; however when 2 field sweep is magnified (X25) the entire
vertical (field) interval can be displayed.
The PAL graticule scales are from 0 to 1.2 V on the left side. See Figure 2-17.
The right side has markings at sync tip (–0.3 V), baseline (0 V), and peak white
(+0.7 V). There are 2% and 4% markings at the horizontal center of the graticule
on the 0 V line (sync tip level) to assist in measuring sync amplitude. The
dashed horizontal line at the top of the graticule is equal to 1.234 V to indicate
peak amplitude of 100% color bars.
Horizontal Scales for
NTSC and PAL Graticules
PAL Graticule Vertical
Scales