Agilent Technologies HP 83711A - INT LEVEL

INT
LEVEL
The
4
INT
LEVEL
5
key
enables
internal
leveling.
Internal
leveling
uses
an
internal
ALC
(automatic
level
control)
detector
to
provide
automatic
level
control
of
the
output
power
at
the
RF
OUTPUT
connector
.
When
the
4
INT
LEVEL
5
key
is
pressed,
the
INT
(ALC)
annunciator
will
be
lit.
Internal
leveling
is
used
to
control
the
internal
RF
signal
over
a
specied
range
(the
vernier
range)
of
0
1
to
+13
dBm. A
dditional dynamic
range
is
provided
by
an
optional
0
110
dB
step
attenuator
(Option
1E1)
to
give
an
eective
dynamic
range
of
0
110
to
+8
dBm (
0 90
to +8
dBm
on
HP
83711A/12A).
An
ALC
unleveled
condition
occurs
when
the
internal
ALC
circuitry
cannot
maintain
leveling.
This
can occur
due to
an
instrument
fault
or
because
the
instrument
is
set
to level
for an
RF
output
level
that
is
beyond
its
capability
.
Calibrated
output
level
is
only
guaranteed when
the
UNL
VL
annunciator
is
not
lit.
When
the
synthesizer
UNL
VL
annunciator
lights,
the
knob
,
arrow
keys
,
or
the
numeric
keypad
can
still
be
used
to
change
displayed
power
up
to
the
maximum
value
.
However
,
the
actual
output
power
will
not
increase
.
Only
the
displayed value
changes
.
The
internal ALC
circuit
maintains
a
constant
RF
power
level
over
frequency
at
the RF
OUTPUT connector
.
The
ALC
circuit
is
a
feedback
control
system
where
output
power
is
measured
and
compared
to
the
desired
power
level.
When
output
power
does
not
equal
the
desired
power
level,
the
ALC
changes
the
output
until
the
actual
and
desired
levels
are
equal.
The
actual
maximum
leveled
power
available
is
dependent
upon
the
frequency
and varies
across
the
range
of
the
synthesizer
.
The allowable range for power level entries (using the
4
POWER LEVEL
5 key) is
0 15 dBm to +30 dBm for standard conguration instruments and
0 120 dBm
( 0 100 dBm on HP 83711A/12A) to +30 dBm if Option 1E1 is installed.
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