Wheatstone E-SAT, Technical Manual

Page: 30 / 126

G E N E R A L I N F O R M A T I O N
page 1 – 22
E-Series Network / Apr 2007
Audio Connections
All audio connections to the E-SAT and MICROSAT are made through
multipin DB-25 connectors located on the rear of the chassis.
The factory supplied hand crimping tool is used for all DB-25 style
wiring connections (see instruction on the page 1-24).
Digital Audio Connections
CABLE - All AES/EBU input and output digital audio connections are
balanced and should be made using a high quality digital audio cable. Be
sure to select a digital audio cable with an integral drain wire of the same
wire gauge (AWG) as the twisted pair as this facilitates an easier and
consistent termination process. Typical AES/EBU digital audio cable has
a very low characteristic capacitance per ft (pF/ft), and a nominal imped-
ance of 110 ohm. High quality digital audio cable offers better signal
transmission performance versus typical analog audio cable, especially
over long cable runs. Check the cable manufacturer’s data sheet to be sure
the cable you plan to use will work in your application.
CONNECTORS - Typically, all AES/EBU connections are made with
the supplied DB-25 male mating connectors. These crimp style connectors
will accept wire gauge 22 - 28AWG.
Unbalanced Analog Connections
ANALOG INPUTS — Wire to the switcher input end with typical
shielded, two conductor cable (like Belden 9451), just as if you were
connecting a balanced source. At the unbalanced source machine’s output,
connect the + output to the HI input wire and connect the source machine
GND wire to LO; connect the shield at the balanced end only.
Note: Unbalanced analog sources typically have -10dBv (316mV RMS)
signal levels and will not match the E-SAT and MICROSAT nominal
operating level of +4dBu (1.23V RMS). We highly recommended that you
first externally balance any unbalanced sources you plan on connecting to
the E-SAT and MICROSAT. Many third party “match boxes” are commer-
cially available for this.
ANALOG OUTPUTS — Use an electronically balanced output circuit
which behaves exactly like the secondary of a high-quality transformer,
with no center tap—this output is both balanced and floating. For unbal-
anced operation, either the HI or LO side of the analog output must be
strapped to ground of the unbalanced input, with the output taken from the
other side. (Normally you would strap LO to ground, and use HI to feed
your unbalanced equipment input.) Leave the SH floating at the unbalanced
end.
Unbalanced Digital Connections (SPDIF)
SPDIF INPUTS - The SPDIF (Sony/Phillips Digital Interface) or
“consumer” digital audio interface is a two wire unbalanced signal typically
on a single RCA style connector. We highly recommend using a “balun” or
E-Series Network / Jan 2008