Orban OPTIMOD 6300, Руководство по эксплуатации

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OPTIMOD 6300 DIGITAL INTRODUCTION
1-11

OPTIMOD 6300 substitutes for the AGC in an Optimod at the transmitter and
provides protection limiting for the STL. Digital output #1 emits the peak-limited
output of the AGC to drive the STL. The AGC is turned off in the transmitter-side
Optimod.
See Studio-Transmitter Link on page 1-12 for more about STLs.
If the STL has at least 16 bits of dynamic range, it is often practical to
drive it with the AGC alone, allowing additional headroom for the over-
shoots that the 6300’s peak limiter would have otherwise removed. De-
feating the peak limiter (by setting the output to
AGC
or Multiband) will
remove about 16 milliseconds of delay from the signal path. Note that
when the limiter is bypassed, the delay is minimum regardless of the set-
ting of the
P
ROC
D
ELAY
controls.
The 6300’s AGC uses the same dual-band, window-gated, matrix technol-
ogy as the AGCs in Orban’s 2300, 5300, 8300, 8382, 8400, 8500, 9300, and
9400 Optimods. It can therefore accurately substitute for the AGCs in
these devices and can help maintain an all-digital signal path throughout
the facility. Because the 6300’s AGC is more advanced than the AGCs in
Orban’s 2200, 8200, and 9200 Optimods, the 6300 can upgrade the per-
formance of these older products when substituted for their AGCs.
Moreover, because the 6300 supports presets that be recalled by remote
control, it can be automatically synchronized to the presets active at a
transmitter-side Optimod when presets are dayparted.
The 6300’s multiband processing is based on the technology used in Op-
timod-FM 8500’s digital radio processing path and will sound similar. To
help you match the sound of an 8400 or 8500, the 6300 provides presets
with the same names as those in Optimod-8400 and 8500. If you are us-
ing a factory preset at a transmitter-side 8400 or 8500, you can recall a
preset with the same name in the 6300 to ensure that the sound stays the
same as it would if you were using an 8400 or 8500 with its internal AGC.
To achieve this match, you must adjust the transmitter-side Optimod’s
input reference level so that the Optimod performs the correct amount
of multiband gain reduction (i.e., the same amount of GR that it would
have performed if its internal AGC were active). This match will occur
automatically if you use the 6300’s tone generator to emit a 400 Hz tone
and then use the tone to calibrate the transmitter-side Optimod. Step (E)
on page 2-22 of this manual describes this procedure for a 6300 at the
transmitter; the procedures for the 2300, 5300, 8300, 8382, 8400, 8500,
9300, and 9400 Optimods are virtually identical and are described in their
manuals.

Digital output #2 emits a peak-limited, multiband-processed signal to drive a
netcast encoder (like Orban’s Opticodec-PC) or a digital radio transmitter.

The analog output emits a low-delay multiband-processed signal with no peak
limiting to drive talent headphones at the studio.
The total input-to-output delay through this path is approximately 5 ms.
While you could also use one of the digital outputs to emit this signal,
this would add about 1 ms of delay because of the additional delay of
the external D/A converter required before the headphone amplifier.