Six Channel Audio Board; Input Connectors; Input Wiring; Unbalanced Audio - Radio Systems Millenium-A Analog Console Installation And Operation Manual

Radio Systems Millenium-A Console
3.1

Input Connectors

Illustration C-1 shows the location of all board input and patch point connectors as well as the pin-outs of the connectors
for 5-pin version consoles. Illustration C-2 shows the location of all board input and patch point connectors as well as
the pin-outs of the connectors for RJ-45 version consoles.
3.1.1

Input Wiring

Every input, from mic thru high level wires to the input connectors. One connector is provided for each channel "A" input
and another is provided for each "B" input. Each connector handles left and right balanced audio from the source equip-
ment.
5-pin consoles provide one ground terminal on each connector for the audio inputs. RJ-45 consoles provide a jumper
behind the input connector to select grounding options. Grounds should be connected at either the console or equip-
ment and not at both ends, to avoid ground loops. The console is usually used as the grounding reference point.
3.1.2

Unbalanced Audio

If an unbalanced audio source is to be connected to the console, single conductor shielded cable or two conductor
shielded cable with a foil shield around each conductor should be used. The audio should be connected to the + input,
while the shield should be connected to both the - input and ground. In this case, the shield is connected at both ends of
the cable.
3.1.3

Mono Inputs

For consoles produced after September, 2008: Inputs can be made mono by installing the mono/stereo select jumpers
as shown in Illustration C-1 (5-pin version console) or Illustration C-2 (RJ-45 version console).
For 5-pin version consoles produced prior to September, 2008: If one input (A or B), rather than an entire channel is to
be fed from a mono source, connect the Left+ input to the Right+ input and connect the Left- input to the Right- input. If
an entire channel is dedicated to mono sources (both A and B inputs) wire the input signal only to the Left Input and refer
to illustration C-1 for proper jumper placement on header J7.
3.2

Input Gain

3.2.1

Channel Sensitivity

The gain of an entire channel or the gain of an individual input can be changed to accommodate any mix of different
input source levels.
Overall channel gain is changed by installing jumpers into gain header J5 for the left channel and gain header J6 for the
right channel. The gain jumpers allow selection of four different overall gain range sensitivities; line (0 to +8 dBv), and
mic (-55 to -35 dBv), low (-20 to -10 dBv), and consumer (-10 to 0 dBv). Mic level sensitivity also requires the use of a
mic level attenuator dip carrier, as described in the next section on input sensitivity.
Changing gain headers effects the gain of the entire channel (both inputs). Refer to illustration C-3 for channel sensitiv-
ity strap programming.
3.2.2

Input Sensitivity

Individual input gains are changed by plugging any of 5 standard input attenuator DIP (IAD) carriers into the channel A or
B input attenuator DIP sockets. The IAD's are used to reduce the sensitivity of an input after it has been increased via
the channel gain straps. This allows the use of sources of radically different output levels on the A and B inputs of the
same channel. An example where an IAD would be utilized, would be to allow a line level source to be connected to a
"B" input after the channel sensitivity had raised to consumer level to accommodate a CD player on an "A" input.
In other words, channel gain straps are set to increase channel sensitivity to accommodate the channel's lowest level
source (such as a mic), and IAD's are used to restore the original sensitivity, or any lower sensitivity for the other chan-

Six Channel Audio Board

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