Wohler VMQ-4 User Manual page 12

VMQ Series User Manual P/N 821504 Rev-D
Please refer to Figure-2b on the following page to familiarize yourself with the rear panel features of the three
VMQ models. The following sections describe these features and are referenced, by letter, to Figure-2b.
A Power Input - IEC-320 Connector
Attach a standard IEC-320 power cord between this connector and mains power (100 - 250VAC, 50/60
Hz). The front panel power LED (Item 6, page 10) will glow green to indicate operating voltages are
present.
B Analog Inputs - Chan. 1-4 - Phoenix or XLR Connector (VMQ-4)
These four inputs are meant to receive standard analog audio signals and are configured for balanced
(100K Ohm) connections. Either Phoenix (standard) or XLR (optional) connectors may be specified at the
time of ordering the VMQ-4. Inputs are labeled 1 through 4. XLR connectors are 3-pin female and
Phoenix Connectors are standard 3-pin type. Pin-out information for Phoenix connectors are silk-screened
above each connector. XLR pin-outs are as follows: Pin-1 = common, Pin-2 = low, Pin-3 = high.
C AES/EBU Inputs and Outputs - Chan. 1-2 - BNC Connector (VMQ-2D)
The two BNC connector inputs (IN 1 and IN 2) are meant to receive standard AES/EBU digital audio
signals. There are also two re-clocked outputs (OUT 1 and OUT 2) derived from the two inputs. All BNC
connectors are female.
D SDI Input and Output - BNC Connector (VMQ-SDI)
The SDI input connector is meant to receive a standard SDI digital audio signal. The output is derived
from the input signal and is re-clocked. Both BNC connectors are females.
E Termination Select - 2-Position DIP Switch (VMQ-2D)
This DIP switch sets the termination characteristics of the AES/EBU input connectors. There are two
switches; one on the left (TERM 1) for the Channel 1 input/output, and one on the right (TERM 2) for the
Channel 2 input/output. In the event that signals entering a channel input are connected to terminated
downstream equipment via the OUT connectors (or external "T" conectors), the DIP switch associated
with that channel should be set to unterminated (UP). If there is no connection to downstream equipment,
then the DIP switch should be set to terminated (DOWN).
F Gain Calibration - 2-Position DIP Switch (VMQ-2D and VMQ-SDI)
Gain calibration, the analog level which corresponds to a given digital value, is settable via this DIP
switch. The factory setting is +4 dB = -20 dBFS. See below or the silk-screen on the rear panel for
settings.
G Converted Analog Out - Phoenix Connector (VMQ-2D)
These connectors output a converted analog signal of the four channels derived from the AES/EBU inputs.
H Analog Out From SDI - Phoenix Connector (VMQ-SDI)
These connectors output a converted analog signal of the four channels derived from the SDI input.
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Rear Panel Features
© 2006 Wohler Technologies Inc. ALL rights reserved
Section 2: Operation