Orban OPTIMOD-AM 9300, Руководство по эксплуатации

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OPERATION ORBAN MODEL 9300
“wideband compression” sound than the other factory presets. Meanwhile, the
multiband compressor is operated lightly with relatively little gain reduction so it acts
more like a limiter than a compressor. Music Heavy is therefore an alternative to
General Purpose Fast, providing a different “flavor” of processing. Either preset could
be used to achieve a highly-processed sound with music programming.
The GREGG preset is designed for general-purpose voice/music programming,
particularly on music-oriented formats. Although not the loudest 9300 preset, it has a
smooth, well-balanced quality that keeps audiences listening. We tuned it to sound
very similar to the legendary Gregg Laboratories 2540 AM processor (designed by
Orban’s Vice President of New Product Development, Greg Ogonowski, in the 1980s),
using a direct A/B comparison with the Gregg processor to ensure accuracy. This
required setting the B1/B2 CROSSOVER to 200 Hz and setting other controls
appropriately.
The PRESENCE preset, as its name suggests, emphasizes the spectrum around 3 kHz.
It is a very loud preset, particularly useful for talk formats. Unlike the “HF” presets,
it is set for full NRSC bandwidth and tuned for a moderate amount of bass.
As always, the actual audio cutoff frequency will depend on the setting
of the bandwidth control in System Setup.
MW stations seeking to increase their coverage and to cut through co-channel inter-
ference are appropriate candidates for this preset, which renders speech crisp, loud,
and highly intelligible.
This preset is targeted for the typical narrowband MW radio and will sound shrill and
unpleasant on wideband radios (of which there are very few in the market). If you feel
that the preset has too much distortion, feel free to turn it down it with
L
ESS
-M
ORE
to
taste. The factory
L
ESS
-M
ORE
setting is 9.0, so there is plenty of room to turn the
preset down without seriously compromising loudness and coverage.
You can also reduce the midrange boost if you feel this is excessive. Part of the boost is
implemented in the Equalization section and part is implemented by the B4 and B5
output band mix controls, which are found in Advanced Control.
HF GENERAL is a 4.5 kHz-bandwidth preset for international shortwave trans-
mission. In recognition of the severe noise and interference problems often
encountered in HF propagation, the
HF GENERAL
preset has been ``tuned" to
emphasize loudness and intelligibility. By comparison to the medium-wave-oriented
presets,
HF GENERAL
has a more ``forward" midrange balance and less bass. This is
because bass costs modulation without contributing proportional intelligibility (it
also can make intermodulation distortion worse during selective fading), and
because a boosted midrange can most effectively cut through noise to provide
intelligibility.
HF VOICE is a 4.5 kHz-bandwidth preset for international shortwave transmission.
Compared to
HF GENERAL
, it emphasizes voice-range frequencies and has less bass.
It is carefully crafted to maximize speech intelligibility in the presence of noise,
interference, and jamming. If you need even more average modulation at the
expense of distortion, turn up
L
ESS
-M
ORE
as necessary.