Racal Instruments 9081 Maintenance Manual page 21

Accuracy:
AMPLITUDE
MODULATION
Frequency Ranges:
Modulation
Depth:
Distortion:
Accuracy:
FSD
Deviation
Front Panel
Meter
frequency response
within
3dB
3kHz 20Hz
-
5kHz
10k
Hz 20Hz - 20kHz
30kHz
20Hz -
100k
Hz
100k
Hz 20Hz
- 100k
Hz
An
external input of
IV
r.m.s.
into
60CQ
gives
full
scale deviation.
±
5
%
of full-scale reading (f.s.d.).
(1)
Using the internal oscillators:
400Hz,
1kHz and 5kHz.
(2)
Using external source d.c.
up
to
100kHz
(9081)
or
20kHz
(9082).
(1)
Up
to
90%
at
a
modulation frequency of
30kHz
or
less,
decreasing
to
50%
at
100kHz.
Adjustment
(internal
source)
is
by
MODULATION
LEVEL
control
.
(2)
Using an external input
800mV
into
60CQ
gives
80%
modulation depth.
At
80%
modulation depth,
using internal
oscillator:-
for carrier
frequencies from 5
to
520MHz,
<
5%
for
carrier
frequencies from
1
.5
to
5MHz,
<
15%
(9082 only).
For
modulation depth
below
80%:-
for
carrier
frequencies from 5
to
520MHz,
±3%
f.s.d.
±2%
of
reading
for
carrier
frequencies from
1
.5
to
5MHz,
better
than
±5%
f.s.d.
±10%
of reading
(9082 only).
9081 and
9082
Vol
.
2
Tech. Spec.
(5)