Tektronix 434, Инструкция по эксплуатации

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h. A D J U S T —C871 and C881 (see Fig. 5-12) fo r best
tim in g and lin e a rity excluding the firs t and last tw o
divisions o f the m agnified sweep.
Calibration—434
i. Set the T IM E /D IV sw itch to 1 ps and the M A G sw itch
to .02 /Us. Set the V O L T S /D IV sw itch to 2 m V /D IV .
j. C H E C K —C R T display fo r tw o cycles per division (one
cycle per divisio n if using a 20 nanosecond sine wave) w ith ­
in 0.4 division (0.5 division if this measurement is being
made outside o f the + 2 0 'C to + 3 0 ° C tem perature range).
Exclude the firs t and last ten divisions o f m agnified sweep.
k. A D J U S T — C871 and C881 (see Fig. 5-12) as neces­
sary fo r the best com prom ise o f tim in g and lin e a rity
between 1 ps w ith 5 0 X m a g n ifica tio n and .2 ps w ith 10X
m a gnification.
40. Check T IM E /D IV Accuracy
a. C H E C K —A p p ly the appropriate tim e marks and
check each p o sitio n o f the T IM E /D IV sw itch fo r proper
tim in g (unm agnified) over the firs t ten divisions o f sweep
w ith in 0.3 d ivisio n (0.4 division if th is measurement is
being made outside o f the +2 0 °C to +30SC tem perature
range).
41. Check M agnified Sweep Accuracy
a. Set the T IM E /D IV sw itch to 1 ms.
b. C H E C K —A p p ly the appropriate tim e marks and
check m agnified tim in g at .5 ms, .2 ms, .1 ms, 50 ps, and 20
ps w ith in 0.4 division (0.5 division if th is measurement is
being made outside o f the +20°C to +30°C tem perature
range).
c. Set the T IM E /D IV switch to .5 ms.
d. C H E C K —A p p ly the appropriate tim e marks and
check m agnified tim in g at .2 ms and 20 ps w ith in 0.4 d iv i­
sion (0.5 division if th is measurement is being made outside
o f the +20°C to +30°C tem perature range).
e. Set the T IM E /D IV sw itch to .2 ms.
f, C H E C K —A p p ly the appropriate tim e marks and
check m agnified tim in g at 50 ps and 5 ps w ith in 0.4 d iv i­
sion (0.5 division if this measurement is being made outside
o f the +20° C to +30°C tem perature range).
42. Check High Speed M agnified T im ing Accuracy
a. C H E C K —T im in g accuracy o f T IM E /D IV and MAG
sw itch com binations given in Table 5-6 w ith in 0.4 division
(0.5 d ivisio n if this measurement is being made outside o f
the +20° C to +30° C tem perature range).
TABLE 5-6
High Speed Magnified Timing Accuracy
T IM E /D IV
M A G
P ortions Excluded
1 MS
.5 ps
F irst and last .5 division.
.2 ps F irs t and last 1 division.
.1 ps F irs t and last 2 divisions.
.05 ps F irs t and last 5 divisions.
.02 ps F irs t and last 10 divisions.
.5 ps
.2 ps F irs t and last .5 division.
.1 ps F irst and last 1 division.
.05 ps F irst and last 2 divisions.
.02 ps F irs t and last 5 divisions.
.2 ps
.1 ps F irs t and last .5 division.
.05 ps F irst and last 1 division.
.02 ps F irs t and last 2 divisions.
b. Disconnect all test equipm ent.
43. Check External H orizontal S ensitivity
a. Set the T IM E /D IV sw itch to E XT H O R I2 and the
TR IGGER L E V E L c o n tro l fu lly clockw ise.
b. C onnect the o u tp u t o f the Standard A m p litu d e C ali­
b ra to r to the E X T H O R IZ in p u t connector via a 42-inch 50
Q. BNC cable.
c. Set the Standard A m p litu d e C a lib ra to r fo r a tw o -v o lt
o u tp u t signal am plitude.
d. C H E C K —C RT display fo r tw o dots h o riz o n ta lly
separated by a p p ro xim a te ly fo u r divisions (ty p ic a lly w ith in
3.5 to 4.5 divisions).
5-26
e. Disconnect all test e quipm ent.