Operating instructions

OPTIMOD-AM DIGITAL INSTALLATION
2-5
8. Install Monitor Rolloff Filter. (optional)
Orban Monitor Rolloff Filters are accessories that can be ordered from your au-
thorized Orban Broadcast Dealer. The Orban model number is MRF-023.
The Orban Monitor Rolloff Filter alters the flat response typical of a modulation
monitor's audio output to one that more closely resembles that of an actual AM
receiver. It is a passive filter, requiring no power supply. Its metal flange is drilled
such that it can be mounted to one rail of a standard rack. (See page 1-23 for
more about studio monitoring.)
A) Select rolloff response.
The Monitor Rolloff Filter is supplied jumpered for NRSC
WITH 10 KHZ
NOTCH, unless otherwise noted.
 NRSC with 10 kHz NOTCH
Accurately simulates the sound of a standard NRSC receiver. Also useful
for remote off-air monitoring because it filters out the 10 kHz whistles
caused by interfering first-adjacent stations (in countries with 10 kHz
channel spacing). Intended to complement the
HF CURVE NRSC setting
in OPTIMOD-AM.
Note that very few real radios have a frequency response resembling the
NRSC standard. Therefore, the NRSC rolloff will result in substantially
brighter sound than most radios provide, and the 18dB/OCTAVE setting
provides a more realistic simulation of a typical radio.
 NRSC: NRSC rolloff without 10 kHz notch.
 18dB/OCTAVE
Simulates the sound of an average narrowband AM/MW receiver except
that it shelves off above 6 kHz instead of continuing to rolloff as a real
radio would. This rolloff complements an
HF CURVE setting of 0 in
Figure 2-4: Jumper Positions, Monitor Roll-Off Filter