Orban OPTIMOD-FM 8600, Operating Manual

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INTRODUCTION ORBAN MODEL 8600
can exaggerate flaws in the source material, it is very important that the source au-
dio be as clean as possible.
For best results, feed OPTIMOD-FM unprocessed audio
.
No other audio processing is
necessary or desirable.
If you wish to place level protection prior to your studio / transmitter link (STL), use
the Orban Optimod 6300 or Optimod-PC 1101 or 1101e. These processors can be ad-
justed so that they substitute for the AGC circuitry in OPTIMOD-FM, which is then
defeated.
The 8600 simultaneously processes for analog FM and digital channels like the iBiq-
uity™ HD Radio™ system, DAB, DRM, or netcasts. The 8600’s HD output provides
look-ahead peak limiting that is optimized to make the most of limited bit-rate co-
decs used in many digital radio systems. By eschewing any clipping, the HD output
prevents the codec from wasting precious bits encoding clipping distortion products,
allowing the codec to use its entire bit budget to encode the desired program mate-
rial.
Thanks to a base sample rate of 64 kHz throughout the 8600’s processing, the HD
output can be set for audio bandwidths between 15 and 20 kHz. Many codecs oper-
ate better when fed 15 kHz audio because this enables them to use their available
bit bandwidth most efficiently by concentrating on the part of the audio spectrum
that is critical to perceived audio quality. This is particularly true for low rates, like
32 kbps. However, at higher sample rates, full 20 kHz bandwidth provides the same
bandwidth as typical source material, so you may prefer to use it for rates of 96 kbps
and above.
OPTIMOD-FM 8600FM is the same as the 8600 except that it does not provide digital
radio processing. The 8600FM can be upgraded to an 8600 in the field by installing
the plug-in CPU board contained in the 8600UPG/HD upgrade kit, which can be pur-
chased from your Orban dealer.
User-Friendly Interface
•
A large 5.7” (quarter-VGA)
color liquid crystal display
(LCD) makes setup, ad-
justment and programming of the 8600 easy. Navigation is by a miniature joy-
stick, two dedicated buttons, and a large rotary knob. The LCD shows all meter-
ing functions of the processing structure in use.
•
Use the Locate joystick to navigate through a menu that lets you recall a preset,
modify processing (at three levels of expertise), or to access the system’s setup
controls.
Absolute Control of Peak Modulation
•
The 8600 provides universal transmitter protection and audio processing
for FM broadcast. It can be configured to interface ideally with any commonly
found transmission system in the world, analog or digital.