Kenwood FC-757, Инструкция по эксплуатации, Страница: 21 / 40

attenuated into 1/10 before reaching the
counter. T h i s attenuates noise-superimposed
input s i g n a l s . In addition, the attenuation
circuit preprocesses a signal w i t h rather a
high amplitude into a reasonal level. A s a
result, accurate counting is assured.
3) - S L O P E s w i t c h
C H A N N E L A - S L O P E s w i t c h © is provided
to select negative-going edge or positive-going
. edge of an input signal to the C H A N N E L A
input juck f o r synchronization.
If t h i s s w i t c h is pressed (
J L
) , negative-going
edge is selected f o r synchronization w i t h the
frequency counter. If pressed again ( M L ) ,
positive-going edge is selected f o r synchroni-
zation w i t h the counter.
Note : If the input s i g n a l s are handled in
the frequency measurement mode and
its measurement mode and its meas-
urement value is displayed in M H z / m s ,
t h i s s w i t c h is bypassed. A s a result,
the count operation is carried out in
synchronization w i t h negative-going edge.
4) Trigger Level A d j u s t m e n t
The trigger level of the input signals to the
C H A N N E L A input juck can be changed by
T R I G L E V E L control ® .
The functions of t h i s control are a s f o l l o w s .
a . If the control is pressed ( P R E S E T p o s i t i o n ) ,
the trigger level is preset to the center
point of input signals to the C H A N N E L A
input juck.
b. If the control is pulled and then rotated,
the trigger level moves to the earlier point
or the later point f r o m the preset center point.
F o r detailed i n f o r m a t i o n , refer to Chapter
6 ' M e a s u r i n g Considerations'.
5 - 2 Period measurement
In the period measurement mode, the cycle time
of each input signal is measured.
The cycle t i m e f i n a l l y output by the counter is
the average of a l l the cycle t i m e s of the
number of cycles handled. The number of cycles
to be measured can be 1, 10, 100 or 1000.
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