Tektronix 434, Инструкция по эксплуатации

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Operating Instructions—434
N O T E
F o r lo w -fre q u e n c y signals b e lo w a b o u t 100 h e rtz , use
th e D C p o s itio n to p re v e n t a tte n u a tio n .
5. Set th e T R IG G E R IN G c o n tro ls to o b ta in a stable
d isp la y. Set th e T IM E /D IV sw itch to a p o s itio n th a t d is ­
plays several cycles o f the w a v e fo rm .
E X A M P L E . Assume th a t the peak-to-peak vertical
d e fle c tio n is 4.6 d ivisio n s (see Fig. 2-7) w ith a V O L T S /D IV
sw itch setting o f .5 V .
V o lts
Peak to Peak
vertical
= d e fle c tio n
(divisions)
V O L T S /D IV
setting
S u b s titu tin g the given values:
6. T u rn the ve rtica l P O S IT IO N c o n tro l so the lo w e r p o r­
tio n o f th e w a ve fo rm coincides w ith one o f th e gra ticu le
lines b e lo w the center h o riz o n ta l lin e , and the to p o f the
w aveform is on th e view ing area. W ith the h o riz o n ta l POSI­
T IO N c o n tro l, m ove the d isp la y so one o f the u pper peaks
lies near the ce n te r ve rtica l lin e (see Fig. 2-7).
7. Measure the divisions o f v e rtica l d e fle c tio n peak to
peak. Make sure the V ariable V O L T S /D IV c o n tro l is in the
C A L p o s itio n .
V o lts Peak to Peak = 4 .6 X 0 .5 V
T h e peak-to-peak voltage is 2.3 volts.
Instantaneous V oltage Measurements—DC
T o measure the DC level at a given p o in t on a w a v e fo rm ,
use the fo llo w in g p rocedure:
1. C onnect th e signal to e ith e r in p u t c o n n e c to r.
2. Set the V e rtic a l M ode sw itch to disp la y th e channel
N O T E used.
This te c h n iq u e can also be used to m ake measure­
m e n ts betw een tw o p o in ts on the w a ve fo rm , ra th e r 3. Set th e V O L T S /D IV sw itch to disp la y a b o u t six d ivi-
than p e a k to peak. sions o f th e w a v e fo rm .
8. M u ltip ly the distance measured in step 7 by the
V O L T S /D IV sw itch s e ttin g . A ls o in clu d e th e a tte n u a tio n
fa c to r o f the probe, if using a probe th a t does n o t have a
scale-factor sw itc h in g co n n e cto r.
Fig. 2 -7 . M e a s u rin g p e a k -to -p e a k v o lta g e o f a w a v e fo rm .
4. Set th e In p u t C o u p lin g sw itch to G N D .
5. Set th e Sweep M O D E s w itch to A U T O .
6. P osition the trace to the b o tto m line o f th e gra ticu le
o r o th e r reference lin e . I f the voltage is negative w ith
respect to g ro u n d , p o s itio n the trace to the to p line o f the
g ra ticu le . Do n o t move the ve rtica l P O S IT IO N c o n tro l a fte r
th is reference line has been established.
N O T E
To measure a voltage level w ith respect to a voltage
o th e r than g ro u n d , m ake the fo llo w in g changes in
step 6. Set the In p u t C o u p lin g s w itc h to D C a n d
a p p ly the reference voltage to the IN P U T c o n n e cto r.
Then p o s itio n the trace to the reference line.
7. Set th e In p u t C o u p lin g sw itch to DC. The gro u n d
reference line can be checked at any tim e b y sw itc h in g to
th e G N D p o s itio n .
8. Set th e T R IG G E R IN G c o n tro ls to o b ta in a stable
d isp la y. Set the T IM E /D IV sw itch to a setting th a t displays
several cycles o f the signal.
2 -1 6
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