Racal Instruments 9081 Maintenance Manual page 134

(33)
Disconnect
the multimeter
and connect
the
UUT 50Q
output socket
to
a
spectrum analyser
which
has
30dB
of input
attenuation selected.
(34)
On
the
UUT
set:-
The
AM
switch
to
OFF
The
OUTPUT
switch
to
X2
The
RANGE MHz
switch
to
256-512
position.
(35)
Tune
the
UUT
across the
range
and
adjust
R94 on the
p.c.b.
(output
amplifier
bias) for
minimum 2nd and 3rd
harmonic
distortion
on
the
analyser display
which
must be
at least
30dB below
carrier level.