Tektronix 1730 Series, Инструкция по эксплуатации

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1730–Series Operating Instructions
2–25
top in increments by positioning the bar to the left or right from the leading or
trailing edge. Note that when the leading and 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 right of the line time distortion structure. These lines are scaled 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 top of the pulse falling within the dashed lines
equals less than 2% K–Factor.
The PAL vertical scale, from 0 V to 1.2 V, is provided on the left side of the
1735 graticule. See Figure 2-18. The NTSC vertical scale is provided on the
right side of the 1735 graticule. It extends from –40 IRE to 120 IRE, in 10–IRE
increments. Black level setup is denoted by a dashed line at 7.5 IRE. There are
2–IRE and 4–IRE markings near the horizontal center of the graticule, on the
–40 IRE line (sync tip) to assist in measuring sync amplitude. This scale is
designed to be used with the 2LINE or 2FLD Sweep rates.
Dual Graticule Vertical
Scales