
The proper trigger l e v e r shown in the figure is
indicated by the broken Sine a t the top.
T h a t i s , it is set a l m o s t above the noise signal
level.
Adjustable into
t h i s level.
P R E S E T - I N level
(average center)
Figure 6. E x a m p l e trigger level adjustment
6 - 6 Self check mode
The self check mode is provided to check the
internal general functions of the FC-757 universal
frequency counter f o r a short t i m e .
(Operational procedure)
(1) Select the C H E C K / 1 0 M H z mode w i t h F U N G
s w i t c h © .
When the universal counters enters t h i s mode,
the counter input is logically connected to the
time base o s c i l l a t o r .
(2) Change the resolution values by using the
G A T E s w i t c h w i t h display unit select s w i t c h @
pressed a f t e r the counter h a s entered the self-
/ check mode, and then v e r i f y t h a t the output
results agree t o those listed below.
Resolution
value setting
Output display
G A T E time
o
* 2
(measurement
interval period)
0.01s/1
0.1s/10
1.0s/100
10s/1000
10000.0 kHz
• 10000.00 kHz •
10000.000 kHz
0000.0000 kHz
( O V E R F L O W
L E D lights up)
0.01
second
0.1
second
1
second
10
seconds
* 2 G A T E L E D (D remains a c t i v e during the
i n t e r v a l period. T h e measurement interval
is 200 milliseconds.
(3) Change the resolution values by using the
G A T E s w i t c h w i t h display unit select s w i t c h ©
37
Содержание FC-757
Страница 9: ...Figure 1 Front panel 9 ...
Страница 17: ...Figure 2 Rear panel 17 ...
Страница 40: ...A p r o d u c t o f KENWOOD CORPORATION 1 7 5 2 chome Shibuya Shibuya ku Tokyo 150 Japan ...