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KRAMER ELECTRONICS LTD. 9
2. If the following recommended actions still do not result in satisfactory operation, please consult
your KRAMER Dealer.
11.1 Power and Indicators
Problem Remedy
No Power
1. Confirm that the rocker switch is in the “ON” position, and that the
switch is illuminated.
2.
Confirm that power connections are secured at the machine and at the
receptacle. Make sure the mains receptacle is active. If still there is no
power, remove power cord from AC outlet and then, using a flat head
screwdriver, remove the fuse holder located directly below the power
connector on your machine. Confirm that the fuse is good by looking
for the wire connected between the ends of the fuse. If the wire is
broken, replace the fuse with another, with the same rating.
11.2 SDI and Video Signals
Problem Remedy
No video or audio
at the output
device.
1. Confirm that your source and output devices are turned on and connected
properly. The input of your machine should be of an identical signal
format or standard as the output of your source. Signals at the output of
your machine should be of an identical signal format or standard as at the
input of your display or acceptor.
2. Confirm that any other device in the signal path has the proper input
and/or output selected.
3. Confirm that the maximum cable length was not exceeded.
Disappearance of the SDI signal may be a result of the “cliff effect”.
11.3 Noise and Hum
Problem Remedy
Noise bars "roll" up
or down in the output
image
or:
Low Frequency Hum
in the output signal
Hum bars (ground loop) are caused by a difference in the ground
potential of any two or more devices connected to your signal path.
Passing that voltage difference through any available interconnection,
including your video cables, compensates this difference.
WARNING!
Do not disconnect the ground from any piece of video equipment in your
signal path!
Check the following to remove hum bars:
1.
Confirm that all interconnected equipment is connected to the
same phase of power, if possible.
2.
Remove equipment connected to that phase that may introduce
noise, such as motors, generators, etc.
3.
Disconnect all interconnect cables and reconnect them one at a
time until ground loop reappears. Disconnect the affected cable
and replace, or insert an isolation transformer in the signal path.