Tektronix 070-8030-01 114 1780R-Series Service Manual, Table 17: Vectorscope Vector Display (Cont.)

Specifications
1–14 1780R-Series Service Manual
Table 1–7: Vectorscope Vector Display (Cont.)
Characteristic Performance
Check Step
Supplemental InformationPerformance Requirement
Display
Vector Phase Accuracy ±1.25_.Measured with color bar signal. 49
Vector Gain Accuracy ±2.5% (1.25 IRE).
Quadrature Phasing ±0.5_.
Subcarrier Regenerator
Pull-In Range
(NTSC) ±50 Hz of FSC.P
AL
in
s
t
r
u
me
nt
s
a
re
t
es
t
ed
to
10 b y y
5
0
(PAL) ±10 Hz of FSC.
10
Hz,
b
ut t
y
picall
y
lock to within
50 Hz.
Pull-In Time Within 1 second, with subcarrier
frequency within 50 Hz (10 Hz for
PAL instruments) of FSC.
Phase Shift with Subcarrier Frequency
Change
(NTSC) ±0.5_ from FSC to (FSC +50 Hz),
or FSC to (FSC –50 Hz).
(PAL) ±0.5_ from FSC to (FSC + 10 Hz),
or FSC to (FSC –10 Hz).
Phase Shift with Burst Amplitude
Change ±2_ from nominal burst amplitude to ±3 dB. Internal or External burst refer- ence. 50
Phase Shift with Input Channel
Change ±2_.CH A to CH B1 or CH B1, CH B2, and CH B3 to each other. With
EXT REF selected.
50
Phase Control Range 360_ continuous rotation. 50
Vector Display
Differential Phase ≤1.
Differential Gain ≤1%.
Measured with 140 IRE (1 V)
linearity signal with 40 IRE
(300 mV) of subcarrier.
Position Control Range
Horizontal ≥1/4 inch (6 mm) from center. 5
1
Vertical ≥1/4 inch (6 mm) from center.
Clamp Stability 1/64 inch (0.4 mm) or less. Center Spot movement with
rotation of PHASE control. 51