H Ig H Resolutio N Ph Ase Measurement - Tektronix 5440 Instruction Manual

O
p
erating Informatio n-5440
10 . Measure th e h
orizontal difference between cor- EXA MPLE : If the swee
p
rate were increased 10 times
res
p
onding points on the waveforms.
with the mag n ifier, the magn ifier sweep rate s h ould be
45°/ d ivision _ 10 = 4.5°/ d ivisio n. Fig . 1-12 shows th e
same sig nals as use
d
in Fig . 1-11, but with t
he Swp Mag
11 . Multi ply the measure d distance (in divisions) by
butto n pu shed in . Wit h α horizontal d
iffere n ce of six
45°/division (sweep rate) to obtain t he exact amou nt of
d
ivisio n s t he ph ase d
ifference is :
ph ase difference .
magnifie d
Ph ase horizontal sweep rate
Difference=difference Χ (degrees/=(6)(45°)=27°
E XA MPLE : Assume α h
orizontal d ifference of 0 .6
.
divisio n with α sweep rate of 45°/
d
ivision as sh ow n in F ig .
(divisio n s) d
ivision)
1-11 .
U
se the formula:
The ph ase
d
iffere n ce is 27° .
Ph ase
h
orizon tal
sweep rate
Difference = differen ce Χ (d egrees/ =(0.6)(45 0 )=27o
(divisio ns) division)
T he p
hase difference is 27° .
H
ig h Resolutio n Ph ase Measurement
C
hann el 1, o r left Chann el 2, or
plug-in ( reference) center plug-in
ι
' Ί
Ι
Ι
Ι
M
ore accurate
d
u al-trace p h ase measurements can be
made by i ncreasi n g the sweep rate (wit h out changi ng th e
variable Sec/Div co n trol setting) . O ne of the easiest ways ι
to i ncrease th e sweep rate is with t
he Sw p Mag (10Χ)
ι
Horizontal
ι
ι 4
difference -~ ι
button on the time-base u nit. The magnified swee
p
rate is
ι ι
automatically indicated by the crt readout and kn ob-s kirt
scale-factor rea
d
out .
Fig . 1-12 . H ig h-resolutio n ph ase dif ference measurement with
increase
d
swee p rate .