Orban OPTIMOD-FM 5500 Operation Manual page 81

OPTIMOD-FM DIGITAL
feat the pre-emphasis in your stereo encoder or if you will use the analog
output for monitoring, set the output F
If you are sending the analog output of the 5500 through a digital link
that uses lossy compression (like MPEG, APT-X, or Dolby), set the output
. Lossy codecs cannot handle pre-emphasized signals.
F
LAT
If you are going to use the analog output for headphone monitoring [see
step (B) below], set the output F
B) Set the AO S
FM: This produces a fully peak-controlled output suitable for driving a
transmitter.
FM+Delay: This produces a fully peak-controlled output suitable for driv-
ing a transmitter. Up to 16 seconds of diversity delay can be applied to
this output. To set the amount of delay, refer to step (F) on page 2-32.
Monitor: If you do not need the 5500's analog output to drive a trans-
mitter, you may configure it to receive the output of the multiband com-
pressor before peak limiting. This signal is suited for driving headphones.
The input/output delay is approximately 3-8 milliseconds (depending on
the setting of AGC C
have a delay of about 15 ms, which most DJs, announcers, and presenters
can learn to use without discomfort (although they may need some time
to become accustomed to it), the low-delay output will cause less bone-
conduction comb filtering. However, in most cases, the low-delay output
will not be necessary to ensure adequate talent comfort.
The normal delay is 15 ms except for "UL" (ultra-low latency) presets,
which have approximately 5 ms delay.
If have set the source to Monitor, be sure to set analog pre-emphasis to
Flat. See step (A).
C) You can use either program material or tone to set your output level (and
thus, your on-air modulation). If you want to use tone, turn on the 100 Hz
calibration tone and set it to 100%.
The peak level at the analog output is now the same as the maximum
peak level under program conditions when the AO P
.
P -
RE E
This peak level should agree with the setting of the AO 100% control. AO
100% is equal to the RMS value of a sinewave whose peak value is equal
to the maximum peak output of the analog output under program con-
ditions if the AO P
= +10.0 dBu, the peak output is 5.77 volts, which corresponds to a
E
sinewave whose RMS values is 4.08 volts. Program material peaks of fre-
quent recurrence will not exceed 5.77 volts peak.
See step (7.H) on page 2-32 for instructions on how to turn on the cali-
bration tone and set its frequency and level.
D) Using the AO 100% button, set the desired analog output level corresponding
to 100% modulation, using units of dBu (0 dBu = 0.775 Vrms).
The most accurate way to set this control is by observing a modulation
analyzer connected to your transmitter.
to FM, FM+D
OURCE ELAY
ROSSOVER
control is set to P
-
RE E
.
LAT
.
LAT
, or M
.
ONITOR
)
T . Even though normal 5500 presets
YPE
-
RE
.
For example, when AO P
-
RE E
INSTALLATION
control is set to
E
-
RE
2-33