pulse of the composite video signal for reference.
The indicated delay is approximately one microse-
cond. The delay is approximately one microse-
cond. In addition to determining the delay
characteristics of the line, the output waveform
reveals any distortion that may be introduced from
an impedance mismatch or greatly attenuated out-
put resulting from an open line.
P U L S E G E N E R A T O R
5000PPS
s e c .
P U L S E W I D T H
INPUT
U L T R A S O N I C D E L A Y
L I N E (5M s e c )
O U T P U T
Fig. 12 Delay line m e a s u r e m e n t s
V I D E O
A M P L I F I E R
U S E 1 / 1 0 P R O B E
F O R B O T H C H A N N E L S
D E L A Y L I N E
* N O T E : S E T T I N G O F V E R T I C A L "
A T T E N U A T O R S S H O U L D B E
T H E S A M E . B U T M A Y V A R Y
W I D E L Y , D E P E N D I N G O N C I R C U I T
T Y P E .
T O H O R I Z O N T A L
A M P L I F I E R
T O V I D E O O U T P U T
A M P L I F I E R
N O T E : N O E L E C T R I C A L C O N N E C T I O N :
P L A C E C L I P O N I N S U L A T I O N O F P L A T E
C A P L E A D O R IN C L O S E P R O X I M I T Y O F
H O R I Z O N T A L A M P L I F I E R T U B E .
Fig. 1 3 Checking " Y " delay line in color television receivers
Improving the Ratio of Desired to Undesired
Signals:
In some applications, the desired signal may be
riding on a large undesired signal component such
as 5 0 Hz. It is possible to minimize or for practical
purpose eliminate the undesired component. F i g .
1 4 shows the oscilloscope settings for such an
application. T h e w a v e f o r m display of C H 1
indicates the desired signal and the dotted line
i n d i c a t e s the a v e r a g e a m p l i t u d e v a r i a t i o n
A D J U S T F O R O N E
C O M P L E T E C Y C L E
A T 50Hz
S I G N A L
50Hz
S T A R T WITH C H O P
C H A N G E T O ADD ( C H 2 P O L A R I T Y
I N V E R T )
Fig. 14
Improving desired-to-undesired signal radio
15
