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AM-10HD / Aug 2008
A M - 1 0 H D G U I
AM Transmission Screen
AM TRANSMISSION MENU
This screen contains all of the controls necessary to select the correct output op‑
erating modes of the AM‑10HD as well as the controls for transmitter equalization. It
also contains the output control for the Digital AES3 output of the analog side of the
processing chain.
Test Oscillator
The built in test oscillator is capable of generating sine wave test signals from 25Hz
to 12.0kHz at modulation levels from 0 to 100%. The oscillator is On when the Test
Oscillator checkbox is selected.
Tilt Test
When checked, clips the Test Oscillator’s waveform at 50% amplitude in order to
create a test signal for the Low Frequency Tilt and High Frequency Correction Equal‑
izer adjustments.
The clipping created by the Tilt Test option is “soft” in order to prevent transmitter
damage due to the excessively fast rise time that a simple square wave signal would
have. It also automatically clips at 50% amplitude to prevent full‑modulation at the test
frequency when Tilt Test is selected.
The Tilt Test option is also used when adjusting the High Frequency Correction
controls to compensate for transmitter and antenna system high frequency limitations.
(See the section under LF Tilt and HF Correct for instructions on how to properly
use the transmission system equalizers.)
Bandwidth
Sets the output bandwidth of the Analog AM processing chain and has six
settings:
Full
Unrestricted 20kHz output bandwidth.
10kHz NRSC Complies to the US NRSC‑2 requirements.
7.5kHz
Bandwidth restricted to 7.5kHz.
6.0kHz CCIR Bandwidth restricted per CCIR regulations.
5kHz
Bandwidth restricted as required for iBiquity AM HD.
4.5kHz
Bandwidth restricted to 4.5kHz.
