A P P L I C A T I O N S
1 . Using an audio signal generator w i t h a pure sinusoidal
signal, apply a sine w a v e test signal to the audio net-
work being tested.
2 . Set the signal generator output for the normal operating
level of the circuit being tested. Observe the circuit's out-
put on the oscilloscope and if the test circuit is overdriven,
the sine w a v e display is clipped and the signal level must be
reduced.
3 . Connect the HOR. INPUT to the output of the test cir-
cuit.
4 . Set the D I S P L A Y MODE to X - Y .
5 . C o n n e c t t h e probe to the input of the t e s t
circuit.
6. Adjust the vertical and horizontal gain controls for a
suitable viewing size.
7 . Some typical results are s h o w n in Fig. 8. If the t w o
signals are in phase, the oscilloscope trace is a straight
line. If the vertical and horizontal gain are properly ad-
justed, this line is at 4 5 ° angle. A 9 0 ° phase shift pro-
duces a circular oscilloscope pattern. Phase shift of less
(or more) than 9 0 ° produces an elliptical Lissajous' pat-
tern. T h e amount of phase shift can be calculated by the
method s h o w n in Fig. 9 .
W h e n , in particular, the M U - 1 6 5 1 memory unit is con-
nected and its M E M O R Y O U T is applied to HOR INPUT,
the phase of t w o memorized w a v e f o r m s can be
calculated.
When three M U - 1 6 5 K - T ) units are used, X - Y operation
between each trace c a n be executed. A t s u c h times,
turn off S M O O T H E R s w i t c h ( 3 7 ) . Refer to I N S T R U C -
TION M A N U A L on M U - 1 6 5 1 in details.
Fig.
8 .
Typicl phase measurement oscilloscope
displays
B
SINE 0 •= —
A
WHERE <t> = PHASE ANGLE
Frequency Measurement
1 . Connect the sine w a v e of known frequency to the ver-
tical input of the oscilloscope and set the D I S P L A Y
MODE s w i t c h to X - Y .
2 . Connect the vertical input probe to the signal to be
measured.
3 . Adjust the vertical input and horizontal input for proper
sizes.
4 . T h e resulting Lissajous' pattern s h o w s the ratio between
the t w o frequencies (see Fig. 1 0 ) .
U N K N O W N F R E Q U E N C Y R A T I O O F
TO V E R T I C A L INPUT. U N K N O W N
S T A N D A R D F R E Q U E N C Y TO
TO H O R I Z O N T A L INPUT S T A N D A R D
S E E NOTE
S E E NOTE
NOTE A N Y O N E O F T H E S E F I G U R E S D E P E N D I N G U P O N
P H A S E R E L A T I O N S H I P
Fig.
1 0 .
Lissajous' waveforms used for frequency
measurement
1 4
Fig.
9
. Phase shift calculation
W :
1
1 : 1
1V4 : '1
6 : 1
NO AMPLITUDE DISTORTION
NO PHASE SHIFT •
AMPLITUDE DISTORTION
NO PHASE SHIFT
180 OUT OF PHASE
NO AMPLITUDE DISTORTION
PHASE SHIFT
AMPLITUDE DISTORTION
PHASE SHIFT
90 OUT OF PHASE
