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b)
Trig
=
Trigger
mode
—
The
generator
will
give
one
complete
cycle
of
output
for
each
pulse applied to
the
TRIG
IN connector. Since the
SWP/GCV
out-
put can be
operated independently,
it
can be used
as a
convenient
source.
Manual
triggering
can be
accomplished
by
rotating
the Trig
Level
Control
(13)
from
full
CCW
to
full
CW. The
SWP/GCV
output
is
a fixed
0
to
5
V
ramp.
c)
Gated
==
Gated
Mode
—
Operates the
same
as
triggered
mode
except
that the generator
will
con-
tinue to
have output
for
die
full
time
that the
signal
at
the
TRIG
IN connector exceeds the
GATING
Level.
See
Trig Level
(13}.
The SWP/
GCV
output
is
a fixed
0
to
5
V
ramp.
d|
Cont
Swp
= Continuous with
Sweep
Mode
—
The
main
generator operates continuously
and
repeti-
tively
sweeps from
the
minimum
to
maximum
frequency
as
determined
by
the
sweep
controls.
In
this
mode
as
in
the following
two
sweep modes,
the
SWP/GCV
output
becomes
the generator con-
trol
voltage
(GCV) which
is
proportional to the
instantaneous
frequency of the
generator.
e)
Trig
Swp
=
Triggered
Sweep
Mode
—
The
main
generator
oscillates
at
the
start
or
low frequency
until
a
trigger signal
is
applied.
The
frequency
then
sweeps
to the
maximum
frequency
as deter-
mined
by
sweep width and
then
returns to
the
low
frequency
until
another
trigger
is
applied.
f)
Swp
Hold
= Sweep
and Hold
Mode
—
The
generator
operates the
same
as
in
triggered
sweep
mode
except
that
the
output remains
at the high
fre-
quency
after
sweeping
for
the duration
of
the
gate
pulse.
When
the gate
pulse drops,
the
output
returns to the
low
frequency
as
set
by
the
fre-
quency
controls.
14.
Trigger
Input
—
DC
coupled
input with
10
k^2
input
impedance.
The
trigger
level
control adjusts the
sensi-
tivity
of the generator to
this
input
signal.
15.
VCG
(Voltage Controlled Generator) Input
—
This
connector
allows external control of frequency.
With
0
volts
in,
the generator
output frequency
is
deter-
mined by
the
frequency range
selected
and
the
fre-
quency
dial
setting.
A
positive
VCG
voltage
will
increase
this
frequency,
and
a negative voltage
wilt
decrease the frequency. Input
impedance
is
5 kO:
16.
Symmetry
Control
—
This
controls the
time sym-
metry between
the
positive
and
negative portions of
the
output waveform.
In
the
full
counter-clockwise
(detent)
position,
the
control
is
disabled
and
the
output
waveform
has
1:1
symmetry
(50-50
duty
cycle).
Rotating the
dial
clockwise
will
vary the
symmetry
from
1:19 through
19:1.
Note:
when
the
symmetry
is
off
the
NORM
(detent) position,
the
output frequency
is
divided
by approximately
a
factor of
10.
This allows
a
minimum
pulse
width
of
50
nanoseconds.
17.
DC
Offset
—
This
rear
panel control
adjusts
the
'
amount
of
DC
or
baseline offset
above
or
below
signal
ground.
The
Detent
position
gives
normal
symmetry
and
as
the control
is
rotated
from
the
maximum
negative
offset
through
zero
offset
to
maximum
positive offset.
18.
Sync
Out
—
This
rear
panel
output
provides
a
square
or rectangular
output
at
the
same
frequency
of the
main
generator.
The
output amplitude
is
approxi-
mately 2
V
p-p
into
son. The
phase
relationship
between
the
sync output and the
waveforms from
the
son
output
is
as
shown
in
Figure
2-3.
2.4
INSTALLATION
CHECKS
This paragraph
outlines
a
quick
checkout procedure
to
determine
if
the instrument
is
operating properly.
Field
calibration
and checkout
instructions are given
in
Section
4
to
determine compliance with
electrical
specifications.
If
electrical
deficiencies
exist,
refer
to the
warranty
on
the
back
of the
title
page.
Use
a
Tektronix
Model
454
oscilloscope
(or
equivalent)
and
a
10
MHz
Counter
-Timer with
5-digit
resolution
when
performing
these
installation
checks.
1.
After connecting the
line
cord to the
ac
line,
set
the
front panel controls
and
switches
as
follows:
FREQ HZ
(switch)
PWR OFF
FREQ
DIAL
(main
dial)
10
WAVEFORM
SELECTOR
(switch)
%
30
V
P-P
MAX
(control)
counterclockwise
SYMMETRY
(rear
panel switch/control)
OFF
DC OFFSET
(rear
panel switch/control)
OFF
OUTPUT ATTEN
(switch)
0
dB
MODE
(switch)
CONT
SWEEP
TIME
(switch)
OFF
VARIABLE
(control)
clockwise
SWEEP WIDTH
(control)
clockwise
2.
Connect
the 50J2
OUT
connector
to the
oscilloscope,
terminated
in a
50-ohm
load.
3.
Set
FREQ HZ
to
X100.
A
1
kHz
sine
wave
with an
amplitude
of
less
than
1.5 p-p
should
be
displayed
on
the
oscilloscope.
2
3
8/73
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