Amber 5500 - Page 13

L/
Amber
model
5500
Owner’s
Manual Version
07
Programmable
Audio
Measurement
System
Section 2
CAUTION
Note that the
input
termination
resistors can
dissipate
a
maximum
of 1 Watt
continuously.
This is
represented
by
the
following
condi-
tions:
INPUT
MAXIMUM
MAXIMUM
TERMINATION
dBm
Volts
600 ohms
+30 dBm
24.5 V ms
150 ohms
+30 dBm
12.3 V
rms
Input
conditions
greater
than
this can
permanently damage
the
termination
resistors. If an
input
is
selected,
a
termination is
on and the
input
conditions
exceed the
1 Watt
limit,
the
instrument will
automatically
disconnect the
termination to avoid
damage.
All
terminations are also
temporarily
disconnected
during
instrument fatal
error states
and reset after
the errors are
cleared.
See Section
1.3
for
more information
On
input
configurations.
2.1.12 DETECTORS
The
5500
has
three
amplitude detectors,
selectable
by
the
user. The detectors
are true
rms,
average
and
quasi-peak.
All
three
detec-
tors are calibrated to read
the rms value
of
a
pure
sine
wave.
True rms
will
yield
the
most accurate results
of a
complex
waveform
such
as
noise or
distorfion.
Average
will allow
comparison
of
readings
with those
from older
average
responding
instruments.
Quasi-peak
measures noise to
particular
standards
such
as CCIR
468-3.
The
choice of one
of three
detector
charac-
teristics is
made
by
the
DETECTOR
button
(above
the
SHIFT
key).
2.1.13
INTEGRATION
Notably
absent
from the
5500
is
any
means
to choose
the
integration
time
(sometimes
called
averaging
time
or
smoothing).
This is
because this
function is
automatically
hand-
led
internally.
Since the
5500
always
measures
the
frequency
of
the
input signal,
it
is able to
choose
the
optimal
time
constants
automatically.
2-11