Wavetek 188, Instruction Manual

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exceed
the
maximum
d
i a l
range of
the selected
frequency range.
Figure
3-4
i s
a
n
o
m
o
gra
p
h with
examples
of
dial
and
volt a g e effects. Example
1
shows that with OV VCG in­
put,
frequency
i�
dete rmined by the mai n dial setting,
2
(linear
mode) or
. 04
(logarithmic
mode)
in this
exam­
ple.
Example
2
shows
that
with
a positive
VCG
i
nput
,
output
frequency
is increased.
Example
3 shows that
w
i
t
h
a
negative
VCG input.
output
fr e
qu
e
n
cy
is
dec reased. (Note
that
the
Output Frequency Factor
col umn value must be
multiplied
by
a frequency r
a
n
g
e
multiplier
to
give the actual
output
frequency.)
MAIN DIAL
SETTING
YCG IN
VOLTAGE
OUTPUT
FREQUENCY
FACTOR
LIN LOG
4
4
- 4
- 3
3 .4
- 2
- 1
- -
- -
, -
2
.04:---:----
0
"
"
....
,
...
.... .... ...
.004
2.0'"
.004 .0004 4.0
LIN LOG
.0004
.004
1
' EXA M P L E 1
- - - - - - - - .04
2.0
MAIN DIAL VCG IN
OUTPUT
FREQUENCY
FACTOR SETTINQ VOLTAQE
LIN
LOG
4 4
3 .4
2 .04
1 .004
. 004 .0004
- 4
- 3
- 2
- 1
0
+ 1 .0
+ 2.0
+ 3.0
+ 4.0
LI N
LOG
.0004 .004
.04 2.0
4
3.0
4.0
Figure 3-4. VeG Voltag.to·Frequency Nomograph
3-4
NOTE
Nonlinear operation may result when the
VCG input voltage is excessive; that is,
when the
attempted
generator frequency
exceeds the range limits.
The
upper limit is
four times the
multiplier
setting, and the
lower limit is 111000th
(linear)
or
1110,000
(logarithmic)
of the upper limit.
The up to 1 000:1
(
l i
n
ea
r
)
or
1 0,000:1
(logarithmic)
VCG
sweep
of the
gene rator frequencies
available in
each
range results
from
a
4V
excursion
at the VCG
I N
c
o
n
­
nector.
With
the
frequency dial set
to
4.0.
excu rsions
between
-
4V
and
OV at VCG IN
provide
the
up to
1 000: 1
(lin)
or
1 0,000:1
(log) frequency
sweep. With
the
dial
set to .004
{linear}
or
.0004
(logarithmic),
ex­
c
u
r
s i o
n
s
between OV and
+
4V
at
the VCG IN provide
up to 1 000:1
(linear)
or
1 0,000 : 1
{logarithmic sweep
within the set
frequency
range.
3.2.4 Sweep Generator Operation
Operation
as
a s
w
e
e
p generator
is similar to
manually
controlled
generator
operation except the main
generator can be repetitively swept
b e
tw
e e
n
two
selected
frequencies either
li
n
e a
r
l
y
or logarithmicly at
a
selected
sweep
rate. The
relationship
of
internal
ramp
and
main ge n e r a t or -
is shown in
figure
3 -5 .
STOP
TI ME
FREQ
GCV
LEVEL
OUT
STAAT
FREQ
LEVEL
I
I
500
ov -I
OUT
t
STAAT FREQ
DIAL SETTING
Figure 3-5. Effect of Sweep Time and Width
on Output Frequency
3.2.5 Waveforms
The
following steps describe
t
h
e
sweep
operation
setup.
Scans
by
ArtekMedia
=>
2011