Omnia 6 Use and Installation Guide – Version 1.00a
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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 back light inverters (the two large, black modules) on the front-panel controller
board have an output of over 1,200 volts AC with the LCD back lights off, and in excess of
600 volts with the back lights on! 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 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.
