Kenwood FC-758, Инструкция по эксплуатации

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Sn the following paragraphs, the relationship
between measurement modes and measurement
delays w i l l be discussed.
1) Frequency measurement mode
The relationship between the operational modes,
resolution values and measurement periods in the
frequency mode is shown below :
Measurement
Resolution
1 Gate Time
Mode
value setting 1 Gate Time
100 Hz
0. 01s
kHz
10 Hz 0. Is
kHz
1 Hz Is
0.1 Hz 10 s
1 kHz
0. 01s
MHz
100 Hz 0. Is
MHz
10 Hz Is
1 Hz 10 s
Prescale input
10 kHz
0. 027s
( C H A N N E L B
1 kHz 0. 27s
INPUT J U C K )
100 Hz 2. 7s
INPUT J U C K )
10 Hz 27s
A s the above table shows, the gate time w i l l be
short if a low resolution value is selected. T h i s
w i l l be helpful in f i n e - a d j u s t i n g an o s c i l l a t o r ,
which requires quick update.
The update interval w i l l be long if a high resolution
value is selected.
2) Period measurement mode
The period measurement mode processes the speci-
fied number of cycles and then outputs the aver-
age cycle t i m e . The desired number of cycles can
be specified by using the G A T E s w i t c h .
The relationship between the number of cycles and
the G A T E s w i t c h is shown the table below.
Resolution
No. of cycles
value setting
measured
0.1 /is
1
0.01
ps
10
0.001
ps
100
0.0001
/is 1000
3) Inter-measurement interval
T h i s interval is f i x e d a t 200 milliseconds in a l l
modes expect event input t o t a l count measurement
and prescale measurement modes.
In prescale measurement mode it is 540ms, and
in event input t o t a l count measurement mode,
counting is continuous.
T h i s fixed interval is independent of gate t i m e ,
number of cycles, or input frequency.
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