Amber 5500 - Page 28

Programmable
Audio
Measurement
System
Section 2
Amber model 5500
Owner’s
Manual Version
07
2.2.12
FREQUENCY
INCREMENT
In addition to the direct
frequency entry
described
previously, generator frequency
may
be
specified
as a
change
relative to the
current value. The
amount of the
change
is
set
by
the
operator by
using
the increment
mode. The
generator
frequency
is
changed
by using
the
UP or DOWN
MODIFY
keys.
To enter
the increment
mode,
push
and
hold
the SHIFT while
pushing
the
FREQ
prefix.
Next enter the desired increment
value and
then the
proper
units terminator. Terminators
may
be
Hz,
kI-Iz or %
(note
that %
is a shifted
function).
For
example,
the increment
may
be
specified
as
100
Hz,
1.1
kHz, 10%, 62%,
etc.
A Hz or kHz value will
yield
linearly
spaced
increments,
% increments
will
yield
log spaced
increments. After the
terminator
key
is
pushed,
the
increment
entry
mode will
be cancelled and the instrument will return
to
the direct
entry
mode. Then the
UP and
DOWN buttons
will increment
(or
decre-
ment)
the
generator frequency
by
the
pre-
viously
specified
incremental value.
Avoid
trying
to increment
to an invalid fre-
quency.
For
example, setting
an increment of
1
kHz,
pushing
DOWN
when the current fre-
quency
is 1 kHz and thus
requesting
a
new
frequency
of
0
Hz
(Error
7).
The UP and DOWN
keys
are
repeat keys.
They
can be held
down for continuous
step-
ping.
The
frequency
will
step sweep up
or
down at
approximately
2steps per
second
after
an initial start
delay
of
approximately
2 seconds. The measurement
circuits of the
meter
may
not
respond
fast
enough
at this
speed
to
allow results to be
displayed
but,
if
the
generator output
is viewed on an
oscillo-
scope,
the
increment
sequence
can be seen.
Or SPCL
function
10
may
be
selected
to
see
the
programmed
(or
set
value)
which will
respond
at the
required speed
to see the
effect.
2.2.13
AMPLITUDE
INCREMENT
The
amplitude
increment mode allows
changing
the
generator output
level
by
a
user
defined value. For
example, stepping
the
output
level in
1
dB,
0.1
dB or
100
mV
steps.
To use the increment mode first
set the incre-
ment value. Push the AMPLITUDE
INCRE-
MENT
prefix
(SHIFT
+ AMPL
keys).
Then
key
in the value and
finally
the terminator.
Valid terminators are
dB,
Volts and %
(remember
that % is a shifted
key).
After
entry
of a
valid increment
value,
the incre-
ment
entry
mode will be cancelled and the
AMPLITUDE mode
automatically
set. Then
the UP and
DOWN
keys
can be used to
step
the
output amplitude
by
the
previously
set
increment.
As
on
the
frequency
mode,
the
UP/DOWN
keys
are
repeat
keys.
Note that the
modify keys
(UP,
DOWN)
act
on
generator frequency
or
generator
amplitude depending
on which
prefix key
has been
pushed.
Each mode
(FREQ
and
AMPL)
has its own stored increment value
which remains until
changed by
the user.
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