Omnia Omnia-6EX, Инструкция по установке и эксплуатации

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Omnia-6ex Use and Operation Manual – V: 1.20
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Electrical and mechanical safety note!
When the Omnia is operated with its chassis top cover removed, you are exposed to potentially lethal voltages and
high speed rotating fan blades.
Before attempting to make voltage measurements, be forewarned that the power supply heat sinks are connected to
the AC power line. The LCD backlight inverters on the front-panel controller board have an output of around 700
volts! Do NOT attempt to measure them.
Avoid these areas whenever the AC power cable is attached to the Omnia. Never attempt to make measurements
when the power supply's safety cover is removed, or near the LCD inverters on the front panel controller PC board!
Be forewarned that the two fans present a serious hazard to fingers, tools, and meter probes. The fan blades rotate at
high speed and have very sharp edges. They can quickly and easily remove a fingertip (gee ... how do we know
this?) Coming into contact with a rotating fan blade will cause serious injury.
When reinstalling the top cover, make certain that all thirty screws are replaced, and that they are tightened to a snug
fit. Operating the unit with its cover removed or without all of the retaining screws will void your warranty and may
compromise the ability of the Omnia to operate in high RF environments.
Narrowing down problems
When actually troubleshooting your Omnia-6, try to ascertain some preliminary information first before embarking
on an in-depth problem-solving mission. Take time to carefully consider whether your unit falls into any of the
following states:
1. The unit is totally dead. Is the power on? Is the line cord plugged into an outlet that has AC power? Is there an
audio input level? Is there an audio output level? Is there a power indication? Are the LCD screens blank,
scrambled, or not illuminated? Symptoms like these might indicate a power supply problem. If you wish to examine
the power supply, be aware that it is switching type, and therefore requires a load in order to start up and operate
properly. Voltages measured when the power supply is not connected to the Omnia motherboard may not be correct.
2. The unit has power, but there is no audio output although the processing bargraphs are working. The first
thing to verify is whether the front panel jog-wheel is operational. Verification of front panel operation helps narrow
down where the problem is. Look at the levels display. If there is input audio but no output audio indications, try
cycling the unit’s power. If that doesn’t bring the operation back to normal, then a hardware failure of some sort has
occurred. If you get output levels but have no output audio, verify that the outputs are connected correctly. An
analog output connected to a digital device, or a digital output connected to an analog device won’t pass audio!
Connect the appropriate test generator to the output cables to verify analog/digital audio is making it to the next
device.
The next condition to check is to see if the failure has caused the processing to cease. Using program material, check
to see if the processing bargraphs are operating. If they are, then it’s a good indication that the basic DSP structure is
sound and the system's host processor is working. At this point, it would be a good idea to see if the loss of audio is
confined to only one output port, e.g. a composite output, the discrete left/right outputs or the AES/EBU output.
Check the signal at each of these locations. If the signal is dead at all three, then this points to a digital audio
problem after the dynamic processing DSP chips. If one of the output sections is not operating, then it can be
localized to that specific section.