Rohde & Schwarz 230.8518, Manual

Page: 25 / 38

Auxiliary
inputs
Apply
a
signal
to the specified points
at approximately
60
kHz and
+6
dEm.
Measure
at the MPX output
EU40.
StllO.7
(E3107 removed
and
ERlOé
inserted).
Sthl.4a (c)
SthlJer (c)
In all three
caSes
the output voltage
must be
+6
dEm
tO.5
dB.
Level adjustment
Apply
L
=
R
=
+6
dEm at 500
HZ. Switch the pilot
off
with 5107.
Measure
at
BU4O
with
a
load
of
600 9.
Adjust
to
+6
dBn (1:0.1
dB) with
R288.
Check
for matching in
the modes
MONO and
STEREO.
Check the
indication in
switch
positions
”MPXl",
”MPXE”
and
"L
+
R”.
5.3.6
Pilot—tone
Generation
Crystal
oscillator
Measure
the
frequency
at test
point
MPlO9, link
3R104
being
set
to
"J“
(as
set in
factory).
Adjust
to
4.256 MHz
’21
x
10'5
with R317.
Pilot indication
Set the
indication selector
(8106)
to PILOT
and the pilot mode
selector
(5107)
to
”on”.
Adjust
for
"9.5”-dBn
indication
on
the
lower scale using
R314.
Pilot
amelitude
Set the indication
selector
(8106)
to PILOT,
do not apply
an
AF signal.
Measure at the multiplex
output
(BU40).
Adjust pilot
indication by
means
of
R514.
Set the pilot
mode
selector
(8107)
to
"on”.
Adjust
for
a
pilot
amplitude
Of
—9.5
dEm
t0.05
dB with R300.
Set the
pilot
mode
selector
(8107)
to
"AqDAU”.
Check
the setting
range
available:
should be
about
—4
dam to ~17
dEm.
Check
the indication
on
the meter.
R
38122
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