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If
the
reading is too high with the INPUT ATTEN fully CCW, and the input
pads
on
Cards # 3TX
and # 4TX
in
the
Main
Chassis
are
strapped
for OdB
attenuation, restrap the pads for 20dB attenuation.)
Turn the Main Chassis LEFT OUTPUT ATTEN fully counterclockwise. Turn on
the
aural transmitter, and advance the Main Chassis LEFT OUTPUT ATTEN
until your TV stereo monitor indicates a L+R modulation of 30%. Record the
reading of the Main Chassis L SYSTEM OUT meter.
Disconnect
the
oscillator
from
the
LEFT
Accessory
Chassis
input,
and
connect
it to the RIGHT Accessory Chassis input. The TOTAL MASTER G/R
meter should still read "0".
Connect
the output of the RIGHT STL receiver to the RIGHT INPUT of the
OPTIMOD-TV
Main
Chassis.
Place
the
VU
meter
FUNCTION
switch
in
R
COMPR
OUT. Adjust
the RIGHT INPUT
ATTEN on
the OPTIMOD-TV Main
Chassis to make the VU meter read 100%.
[NOTE:
The
instructions
immediately
below
apply
only
if
the
output
amplifiers
are
strapped
in
L/R
mode -- see
( 4)
in
Initialization Options in
Part 3 (Installation). If the output amplifiers are strapped in L+R/L-R mode
and
tone
is
applied
to
only one
input channel of the 8182A,
first set L+R
modulation
to
30%
by
adjusting
the
L+R
OUTPUT
ATTEN.
Then
optimize
separation
by
observing
the
undriven
channel
on
your
stereo
monitor
and
adjusting
the
L- R
OUTPUT
ATTEN
until
the
undriven
channel
nulls.]
Advance
the
Main
Chassis
RIGHT
OUTPUT
ATTEN
control
until
your
TV
Stereo Monitor indicates a L+R modulation of 30%.
Check the reading of the Main Chassis R SYSTEM OUT meter. It should be
very close to the reading obtained on the L SYSTEM OUT meter immediately
above.
If
not,
there
is
a left/right
gain
imbalance
in
the
system
beyond
OPTIMOD-TV which should be corrected.
(NOTE:
The " 30%
modulation"
figure
is
somewhat
arbitrary,
as
the
appropriate figure will depend upon the overshoot performance of the lowpass
filters
within
the
external stereo generator,
upon
the
time constant of
the
peak
flasher
in
the
stereo
monitor,
and
upon
whether
the
external
stereo
generator is being used with or without its internal preemphasis. If the stereo
generator's internal preemphasis is not used, modulation is better controlled
and
a higher percentage
of modulation can be
chosen when aligning
with a
lkHz tone in the procedure above.
The " 30%
modulation"
figure
must
therefore
be
modified
in
your
individual
installation according to experience.)
3.b)
Mono Installation Only: Continue to drive the LEFT Accessory Chassis input
with
a lkHz
tone
at a level which produces a " 0" reading
on
the TOTAL
MASTER
G/R
meter.
Connect
the output of
the STL
receiver to
the LEFT
AND RIGHT INPUTS of the OPTIMOD-TV Main Chassis in parallel. Place the
VU
meter
FUNCTION
switch
in L COMPR
OUT.
Adjust
the LEFT
INPUT
ATTEN on the OPTIMOD-TV Main Chassis to make the VU meter read 100%.
Then place the VU meter FUNCTION SWITCH in R COMPR OUT and adjust
the RIGHT INPUT ATTEN on the Main Chassis
to make the VU meter read
100%.
4-3
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