Wavetek 188, Instruction Manual

Page: 19 / 50

Scans by Artekmedia
=>
2011
Connector Impedance
500 OUT
(HI)
. .
.
. . . . . .
.
. .
.
.
.
. . .
.
. .
.
.
. . .
. .
.
SOD
500 OUT
(LO)
. .
.
.
.
.
.
.
.
.
.
. .
.
. . . . .
.
.
.
. .
.
.
. . .
SOO
SYNC OUT
(ITL)
.
.
. . . .
. . . .
. . . . .
. .
.
. .
.
.
.
.
, . . . *
TRIG IN
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
*
VCG
IN
. , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
kO
SWP OUT
.
.
.
. . .
.
.
.
.
.
. .
.
. .
. . .
. .
. .
. .
.
. .
.
.
.
6000
GCV OUT
,
' . . . . , . . , . . . . . . . . . . . . . . . . . . . . . 6000
*The TIL
OUT connector is diode
p rotected
and
can
drive
up
to
20 Transistor-Transistor-Log ic (TTL) loads
(low
level between OV and 0.4V, and high
l
e
ve l bet­
ween 2.4V
and 5V). It
should not be
connected to
resistive load
less
than 6000. The
TRIG
IN
connector
accepts TIL
logic l evels,
is diode protected, and
re­
quires
500
pA
drive from
a
high level output.
MODEL 188
RG58 OR
OUTPUT
EQUIVALENT
IMPEDANCE
500
RECEIVI NG
INSTRUMENT
EFFECTIVE
CIRCUIT
RESISTANCE
OUTPUT
AMPLIFI ER
Figure 3·2. Signa' Termination
3.2.2 Manua' Function Generator Operation
For basic operation,
sel ect
the waveform frequency
and
ampl itude .
The
followi ng
steps
demonstrate
manual control
of the
function
generato r. (Bold
numbers are keys
to
figure
3-1 .)
Step
Setting
500 OUT 15
18 Connect
circuit
to
either
output
(refer to para-
graph
3.2.1 ).
2
FREQUENCY
Set
to desi red
range
of
fre-
MULTIPLIER 4
q uency .
3
Frequency Dial 1
Set to desired frequency
within the range.
4
SWEEP's CONT 5 Extended.
5
FUNCTION
12 Set to
desi red
waveform.
6
DC OFFSET 1 3 Set
as desi red.
Limit
wave-
form amplitude to prevent
clipping
(
s
e
e
figure 3-3).
7
AM PLITU D E
14 Select for
des i red ampli-
tude.
3.2.3 Voltage Controlled Function Generator
Operation
Operation as
a
voltage controlled
function
generator
(VCG)
is as for
a manually
control/ed function
generator, only
the
frequency within particular
ranges
is
additionally
controlled
by
an
external voltage
(
±
4V
excursions) i njected
at the VCG IN
connector.
Per·
form the steps given In paragraph
3 . 2 . 2 ,
only
set
the
frequency
dial
to determine a
reference
from which
the frequency is to be voltage
control led .
OV - -
-
.'"7\[\;------------
_ _ _ _ _ _ _ _ _ _ _ _
V1
_ _
POSitivE NEGATIVE
DC OFFSET DC OF FSET
+5V -'V v - - ----
- -----
_ ,v
_ _ _ _ _ _ _ _ _ _
AI1L
EXCESSIVE
POSITIVE
OFFSET OR
LOADING
EXCESSIVE
NEGATIVE
OFFSET OR
LOADING
Figure 3-3. DC OFFSET Control
1
.
For
frequency
control with
positive dc inputs
at
VCG
IN,
set
the dial
for
a lower
frequency
limit.
2.
For frequency
control
with
negative
de
inputs
at
VCG
I N ,
set the dial for
an
upper
frequency limit.
3.
For modulation with an
ae
input at VCG
I N , s
e
t
the dial at the
desi red center
frequency. Do not
3-3