Sweep Generator Operation - Wavetek 180 Instruction Manual

MAIN DIAL
SETTING
2.0
1.8-f-
1.6
1.4
1.2--
1.0
.8--
.6
.4
.2
.002-'-
VCG IN
VOLTAGE
-2.0-|-
-1.6 - -
-1.2--
- .8
- .4^
^ , EXAMPLE 1
X U-t-
\ + .4--
\
+1.2-
S-?!.
son OUT
FREQUENCY
FACTOR
-.002
-.2
-.4
-.6
-.8
-1.0
--1.2
-1.4
-1.6
+1.6-1-
\
\
-1.8
-2.0 +2.0-'-
Figure 3-6. VCG Voltage-to-Frequency Nomograph
The up to 1000:1 VCG sweep of the generator frequencies
available in each range results from a 2V excursion at the
VCG IN connector. With the frequency dial set to 2.0,
excursions between —2V and OV at VCG IN provide the up
to 1000:1 frequency sweep. With the dial set to .002,
excursions between OV and +2V at VCG IN provide the up
to 1000:1 sweep within the set frequency range.
3.2.4 Sweep Generator Operation
Operation as a sweep generator is like operation as a manual
function generator, only the frequency is automatically and
repetitively swept from the set frequency to a higher fre
quency. Actually, an internally generated positive-going
voltage ramp {available at the SWEEP OUT connector) can
be modified in amplitude and used like a VCG input voltage
to sweep the output frequency (see figure 3-3). Perform the
steps in paragraph 3.2.1 and the following steps for use as a
sweep generator:
Step Control/Connector
SWEEP WIDTH
SWEEP RATE
Setting
As desired. This determines
the upper frequency of the
sweep.
As desired. This determines
the speed of the sweep.
NOTE NOTE
Nonlinear operation results when the VCG input
voltage is excessive; that is, when the attempted
generator frequency exceeds the range setting
(2 times the multiplier setting) or in the other
direction, 1/1000th of the range setting.
To monitor the ramp generator, use the SWEEP
OUT connector. To monitor the frequency of
the main generator, use the GCV OUT connector,
which is a voltage proportional to the generator
frequency.
3-4