Trio CS-2100A, Инструкция по эксплуатации

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APPLICATION
Read the dial setting when B sweep points of
DELAY TIME MULTIPLIER ® and © are in
the same position.
[ E X A M P L E ]
For the example, t h e first dial reading is 0 . 7 6 and the second
is 6 . 2 2 w i t h t h e A S W E E P T I M E / D I V set at 2
M
s .
W e have, substituting the appropriate values
Pulse repetition t i m e = ( 6 . 2 2 - 0 . 7 6 ) x 2 (MS)= 10.92/xs
USING DELAYED SWEEP FOR
MEASUREMENT OF RISETIMES AND
FALLTIMES
Risetimes and falltimes are generally measured by using the
1 0 % and 9 0 % a m p l i t u d e points as reference starting and
e n d i n g points for the rise or fall.
1. A p p l y t h e signal t o the I N P U T and set t h e V M O D E t o
the channel t o be used.
Use V O L T S / D I V and V A R I A B L E t o o b t a i n a normal 6
division high w a v e f o r m display.
Using the # POSITION control, set the w a v e f o r m
position in the central area of the screen vertically, that
it t o coincide w i t h t h e 1 0 0 % and 0 % lines o n t h e CRT
screen.
Set the S W E E P T I M E / D I V t o as high a speed as
possible.
Set A V A R t o the C A L position.
3. Pull o u t the B SLOPE control t o initiate the S T A R T S
AFTER D E L A Y m o d e of operation and adjust the B
S W E E P T I M E / D I V for as short as possible an intensified
section of w a v e f o r m .
4. Using t h e D E L A Y T I M E M U L T I P L I E R , adjust the
w a v e f o r m such t h a t t h e 1 0 % point is intensified and
record t h e dial reading.
5. Similarly, using the D E L A Y T I M E M U L T I P L I E R adjust
t h e 9 0 % point so t h a t it is intensified and record t h a t
dial reading as w e l l .
The pulse risetime (or falltime) is simply t h e difference
b e t w e e n t h e t w o dial settings t i m e s t h e A S W E E P
T I M E / D I V control setting.
Using the f o r m u l a
Risetime = (2nd dial r e a d i n g - 1st dial reading) x Delayed
s w e e p t i m e (A S W E E P T I M E / D I V setting)
[ E X A M P L E ]
For the example, the first dial reading is 1.20 ( 1 0 % point)
and the second is 7 . 3 8 ( 9 0 % point) w i t h the A S W E E P
T I M E / D I V set at 2/is.
S u b s t i t u t i n g the given value:
Risetime = ( 7 . 3 8 - 1 . 2 0 ) x 2 (us) = 12.36MS
TIME DIFFERENCE MEASUREMENTS
USING DELAYED SWEEP
Synchronized w a v e f o r m s w h i c h are s k e w e d in t i m e can be
accurately m e a s u r e d using the delayed s w e e p .
1. A p p l y the t w o signals t o t h e C H 1 and C H 2 INPUTS,
setting the V M O D E t o D U A L and selecting either A L T
or C H O P display.
2. Set the S O U R C E t o the signal t h a t is leading in phase
and adjust V O L T S / D I V and S W E E P T I M E / D I V for easy
w a v e f o r m observation.
Set the A V A R control t o CAL.
3. Pull o u t the B SLOPE control t o initiate the S T A R T S
AFTER D E L A Y m o d e of operation. Set H O R I Z O N T A L
D I S P L A Y t o A - I N T - B and adjust t h e B S W E E P
T I M E / D I V and D E L A Y T I M E M U L T I P L I E R t o m a k e the
intensified portion coincide w i t h the rising edge or fal-
ling edge of the w a v e f o r m t h a t is t o be used as t h e
reference.
4. Set t h e H O R I Z O N T A L D I S P L A Y t o A L T and use t h e *
T R A C E SEP control t o adjust t h e B s w e e p for easy
observation.
5. Using the D E L A Y T I M E M U L T I P L I E R adjust t h e pulse t o
any convenient vertical g r a d u a t i o n line and record the
dial reading at t h a t point.
6. Using the D E L A Y T I M E M U L T I P L I E R adjust t h e cor-
responding point o n t h e second signal t o t h e s a m e
vertical line a n d record t h e reading of t h e dial at this
point as w e l l . The t i m e difference or s k e w of t h e t w o
w a v e f o r m s is t h e n the second dial reading m i n u s t h e
first dial reading multiplied by t h e A S W E E P T I M E / D I V
control setting.
5-11
Rise time