USL JSD-100 Manual - Manual (Page 17)

Page 16
PA Microphone Input. Plug a PA microphone in to the combination XLR / ¼” phone jack. The microphone
input may be configured to drive the main or the surround speakers. In addition, the PA microphone input can
drive the RTA for room equalization.
RTA Microphone Input. The RTA microphone input can drive the real time analyzer for room equalization.
The jack is a 3.5mm stereo jack with the high side of the microphone connected to tip and the low side to
sleeve. The connector ring is driven with +10V through 2.2k to power a preamp in the microphone.
6.6
Analog Audio Output Connections
Depending on which analog output module is installed, the JSD-100 provides eight or sixteen main channel outputs
plus HI and VI-N outputs. All outputs are balanced and may drive balanced or unbalanced loads. When driving
unbalanced loads, run two conductor shielded cable and connect the “ – ” terminal of the JSD-100 output to the
low side of the unbalanced load at the load instead of at the JSD-100 to minimize ground loop noise.
Main Audio Outputs
The main audio outputs are on a module that can be replaced from the rear. A variety of output modules are
available, including 8 channel analog, 16 channel analog, and 32 channel AES. Note that the 16 channel analog
output module supports crossovers. To allow for proper bypass operation, a passive crossover is included. For full
band operation (crossovers not currently implemented), set all four DIP switches to OFF and set the MID and HIGH
trim pots to full counter-clockwise. Adjust the LOW trim pot for the desired full range bypass audio level.
Remember that the front panel fader also affects output level when in bypass. The connections for these output
modules are detailed in Appendix A.
HI/VI-N Outputs
The JSD-100 has balanced HI and VI-N outputs that can drive balanced or unbalanced loads. As with other outputs,
the use of twisted pair shielded cable is suggested whether the load is balanced or unbalanced. When driving an
unbalanced load, connect the “ – ” output of the JSD-100 to low side of the unbalanced input at the destination
end of the cable to minimize ground loop noise. The source of audio to drive the HI and VI-N outputs is
configurable on a per-format basis. The VI-N audio output is typically driven by AES input 16. The HI audio output
can be driven from AES inputs 7 or 15, or from a main audio mix. The USL supplied ferrite block should be clipped
on to the cables adjacent to the connectors to comply with FCC and CE emission requirements. See Appendix A for
pin out information.
6.7 Automation Interface
The JSD-100 includes the traditional parallel automation interface plus RS-232 and Ethernet.
Parallel Interface
Pins 1 through 10 of the DB25F automation connector are “control” pins that accept contact closure or open
collector pulses to ground to select formats. On a format change, the corresponding pin is also pulsed low allowing
this interface to drive other equipment. Pulsing pin 11 low toggles the mute state. Pins 14 through 24 are “status”
pins. One of the pins 14 through 23 is pulled low continuously by the JSD-100 to indicate the selected format.
These pins could drive LEDs with a 470 ohm series resistor to provide a remote format indication. The JSD-100
pulls pin 24 low when the system is muted. Pins 1 through 11 are internally pulled up to +8.4V. They each source
400uA when grounded. A pin needs to be pulled below 2.6V for 10ms or more for the JSD-100 to recognize it as
low. On a format change, the JSD-100 pulls the appropriate pin low for 500ms. +5V at 100mA is available on pin 13
to drive external LEDs or relays. The individual control and status outputs can sink up to 150mA with an open
circuit voltage of +12VDC for inductive loads like relays or +24V for non-inductive loads (indicator lamps, etc.). Pin
12 is the “automation return.” Use this as the low side of switches and indicators instead of using chassis ground.
It is ground through a 10 ohm resistor to limit ground loop current. The USL supplied ferrite block should be
clipped on to the cables adjacent to the connectors to comply with FCC and CE emission requirements. See
Appendix A for pin out information.