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AM-10HD / Aug 2008
G E N E R A L I N F O R M A T I O N
Where to Install the AM-10HD
For best modulation control, in our opinion, the only suitable location for the
AM-10HD is at the transmitter site.
If the AM-10HD must be located elsewhere, the quality of the interconnect-
ing link is critically important. In fact, the requirements for remotely locating
an AM audio processor uniquely parallel the requirements for transmitting an
FM audio processor’s composite baseband signal to a remote transmitter site.
Therefore telco lines, compressed STL’s, and the like should never be used to
carry the processed output of the AM-10HD to a remote transmitter location.
It is better in these instances to carry the unprocessed audio on such links and
install the processor at the transmitter site.
We cannot recommend any other location for the audio processor, including
those associated with various STL’s.
EAS – United States Emergency Alert System
If the EAS generator is placed before the AM-10HD, the levels of the signaling
tones and FSK data may be disturbed by the processing. Therefore it is highly
recommend that the EAS unit be placed after the processing.
If the EAS unit must be installed prior to it, the AM-10HD should be configured
so that when the EAS tones are being sent the AM-10HD is switched to a bypass
or special preset mode. This can be accomplished by using the AM-10HD’s GPI
interface and by assigning a special preset to the EAS function that has internal
processing defeated and audio levels calibrated to provide proper modulation
levels during EAS transmissions.
Arbitron People Meter
The AM-10HD favorably passes the data watermarking scheme used in the
Arbitron rating service People Meter technology regardless of the aggressiveness
of the audio processing performed.
Energizing
Assuming the AM-10HD Digital Audio Processor is correctly rackmount-
ed, you may now energize it. There is no power switch. The AC line input
voltage may be between 90 and 260VAC, 50 or 60Hz. Power consumption is
under 100VA.
Aggressive AC input filtering is utilized at the AC input of the AM-10HD;
however, as mentioned previously, it is always preferable to use external surge
protection and/or an uninterruptible power supply (UPS), especially where AC
power quality is questionable, such as at a remote transmitter site.
Power conditioning, surge suppression, and even power backup devices are
wise investments when using sensitive modern electronic devices that use an
internal computer.
Use of a UPS (uninterruptible power supply) is a good idea and will protect
the AM-10HD from short duration power interruptions which may cause it to
reboot. During boot up, audio is interrupted for approximately 20 seconds.
