— 9 —
fuseholder on the rear panel. Use a small screwdriver to set the
switch for
115V
or
230V
operation.
Mains Fuse
It is important to install the appropriate fuse as noted on the
rear panel next to the fuseholder: 1/4A for 115V mains, 1/8A
for 230V operation. Fuses are the GMA/S500 type (5mm X
20mm size, ‘fast blow’).
Power Cord
The detachable IEC-type power cord supplied with the JUSTIN
808 is fitted with a North-American-standard male plug. If you
need to replace the mains plug with another, you will find that
the individual cord conductors are color-coded in one of two
ways. US standards specify black for AC ‘hot,’ white for AC
neutral and green for earth ground. European CEE standards
specify brown for AC ‘hot,’ blue for AC neutral and green with
a yellow stripe for earth ground. Please keep these straight.
Brownout
Detection
Although the JUSTIN 808 power supply and digital logic cir-
cuits will operate at AC mains voltages below nominal, the
graphic display and LED readouts would fail to give consistent
indications at very low mains voltages. A ‘brownout’ detector
reboots the unit at a mains voltage somewhat below the “low
line” value given in the product specification.
CONNECTIONS
Antenna Input
The antenna input for the internal off-air receiver is a 75-ohm
‘F’ connector. To operate at the peak of its autocorrelation per-
formance, the JUSTIN 808 requires a solid incoming RF signal
devoid of multipath artifacts. Installed at a studio location, a
rooftop antenna aimed at the transmitter is recommended. But
when the unit is co-located with the transmitter, a short length
of wire dangling from the antenna connector may well suffice.
The
FM
and
HD
signal bars on the
Tuner
menu should both be
within a bar or two of the top.
AES Program
Audio Loop-
Through
The JUSTIN 808 may be connected either in the HD1 program
audio signal path or in the FM program audio signal path. This
is an AES3 digital audio connection with the standardized HD
Radio digital audio sampling rate of 44.1kHz.
For reasons stated in the Quick-Start Setup section, the pre-
ferred connection for the JUSTIN 808 is in the HD1 digital audio
feed to the HD exciter or exporter. Interconnection for this
mode is diagrammed on Page 12. The audio gain for the AES
digital audio loop-through can change as much as ±6dB if AGC
is enabled for FM/HD1 level-matching.
The alternate connection, with the JUSTIN 808 in the digital au-
dio feed to the FM audio processor, is also diagrammed on Page
12. In this mode the JUSTIN 808 maintains unity gain for the
AES digital audio loop-through.
Содержание JUSTIN 808
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