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Les langues disponibles
Les langues disponibles
log f
f
STOP
T-
sweep
range
f START
sweep
time
(PERIOD)
l
Hz
fSTART
I
100
1 k
10
k
20
k
SWP
STOP/ START
I
I
Example for the sub-range II (x1 00);
10 k
Hz
100
10
the other two ranges to be regarded similarly.
13
3.2.4.
External sweep and frequency modulation
The SGLE SWEEP button must be released.
The frequency of the generator can be controlled by supplying an external voltage to the SWP VOLTAGE
IN/OUT socket. The frequency of the generator changes exponentially with the control voltage (1 Dekade/1 V),
as described in chapter 3. 2. 3.
Within the frequency ranges some limitations have to be taken into account:
The start frequency limits the maximum external control voltage. A start frequency of 2 kHz for instance
results in a maximum possible sweep range of 1 decade up to higher frequencies, corresponding to a con-
trol voltage of +1 V, example 1 a of the figure. Down to lower frequencies a maximum voltage of- 2,3 V
is permitted not to exceed the limit for the stop frequency of 10 Hz, example 1 b. Is the start frequency
the lower limit of the sub-range (e.g. 10Hz in II, example 2) , the maximum control voltage of +3,3 V
can be made use of.
Example for frequency modulation:
Adjusting the basic frequency to 2 kHz and applying an external d.c. control voltage of-1 V result in a
center frequency of 2oo Hz. Superimposition of an a.c. control voltage of 1 Vpp effects a frequency
modulation within the limits of 2o Hz and 2 kHz, example 3.
j
Hz
fsTART
Uc
f
STOP
for sweep
example
f
0
forFM
2
3,3
v
10~----~~----~----------~*
20
k
100
1 k
2 k
10k
20k
Example for the sub-range II (x100);
10
k
2
k
1
k
200
100
10
the other two ranges to be regarded similarly,
Uc scale reading to be unchanged.
Hz
1
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