ATI Audio DDA208-BNC - Manual (Page 4)

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POWER SUPPLY
Power transformer primary windings are paralleled for 115VAC or wired in series
for 230VAC. Internal jumpers allow field modification if necessary. See below for
voltage conversion instructions.
INSTALLATION
LOCATION
To avoid addition of jitter (timing variations) to the digital bitstream, which could
cause noise and distortion in the recovered audio, avoid locating the DDA in
close proximity to a high energy, high frequency switching type power supply or a
power amplifier that utilizes a switching supply. If possible, do not power both
devices from the same AC power line.
Expensive components start to die at internal temperatures above 70°C (158°F).
We recommend that you maintain rack temperatures below 50°C (122°F) to
prevent excessive internal temperature buildup. This is another good reason not
to mount the DDA directly above that 500W power amplifier.
POWER
If it is necessary to convert a unit wired for 115VAC to 230VAC operation, unplug
the unit from the power source, remove the cover mounting screws and locate
the jumpers next to the power transformer. Clip the jumpers 1-2 and 3-4 (don’t
unsolder), jumper from 2-3 carefully soldering together the free ends of 2-3
previously clipped. This procedure is recommended to avoid soldering damage to
the multi-layer PC board.
WIRING
XLR types require special controlled impedance, 110 ohm, low loss, foil shielded,
twisted pair cables. Standard audio cable is not recommended except for runs of
only a few feet. Belden and most other cable manufacturers offer special digital
audio cabling for this application. With equalization, cable runs of 300 meters
(about 1000 feet) should be achievable. BNC types use 75-ohm coax (RG59).
Select a cable for losses less than 20dB at 12MHz (for data rates up to 96kHz) at
the maximum distance you require. Runs up to 1000 meters should be readily
achievable with low loss coax.