Inovonics AARON 650, Инструкция по установке и эксплуатации

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Ground Loops
Because the unbalanced composite/MPX outputs of the AARON
650 are referenced to chassis ground, a mains frequency or RF
ground loop could be formed between cable shield grounds and
the AC power cord ground. A ‘ground-lifting’ AC adapter may
remedy such a situation, although the chassis must somehow
be returned to earth ground for safety. Generally, being
screwed-down in the equipment rack will satisfy the safety re-
quirement.
ANTENNA INPUTS
ANTENNA 1
and
ANTENNA 2
are relay-selected 50-ohm ‘N’ con-
nector inputs to the receiver. Either input may be selected and
is automatically assigned to that station preset (Page 23). The
antenna that is not selected is terminated in a 50-ohm resistor.
PROGRAM LINE OUTPUTS
AARON 650 digital and analog line outputs are available simul-
taneously with independent settings.
AES Digital
Line Output
The male XLR connector labeled
AES DIGITAL OUTPUT
is a bal-
anced, transformer-coupled digital stereo program output con-
forming to the AES3 (AES/EBU) specification. This is a 24-bit
output at a sampling rate that may be set to 32kHz, 44.1kHz,
or 48kHz under the
Setup / Digital Audio Output
menu.
This menu also sets the digital output level. The dB notation
below the slider control corresponds to the level of program
peaks at 100% modulation (±75kHz carrier deviation). The out-
put may be adjusted between 0dBFS (digital full-scale) and
–30dBFS.
De-Emph
(de-emphasis) may be set either
On
, which follows the
regional standard (Page 23), or Off for an output that will retain
the transmitted FM pre-emphasis curve. Your selection will de-
pend on whether an exciter fed by the AARON 650 has an in-
ternal pre-emphasis network or depends on a pre-emphasized
feed.
Analog
Line Outputs
Male XLR left- and right-channel
ANALOG OUTPUTS
on the rear
panel are electronically-balanced. This means that they are
ground-referenced and not transformer-isolated.
Under the Setup / Analog Audio Output menu, left and right line
outputs may be adjusted to any level between –20dBu and
+18dBu. The dB levels shown below the slider control repre-
sent the unloaded output level at ±75kHz carrier deviation. The
outputs have a resistive source impedance of 200 ohms, with a
100-ohm ‘buildout’ resistor in each leg. When feeding a 600-
ohm load the actual dBm level will be 2.5dB below the Analog
Level
shown under the slider.