User's Manual
Kramer Electronics Ltd. 
18 
Figure 
12
: SG-6N Fuse Location 
10.2   Video Signal 
Problem Remedy 
No video at the output 
device 
1.  Confirm that your source and output devices are powered on and 
connected properly. The input of your machine should be of an identical 
signal format at the output of your source. Signals at the output of your 
machine should be of an identical signal format as at the input of your 
display. 
2.  Confirm that any other device in the signal path have the proper input 
and/or output selected. 
3.  Use the Video Tester to help trace faulty cables and equipment (see 
section 4.1). 
Video level is too high or 
too dim. 
1.  Verify that the lines are well matched through 75ohm impedance; 
otherwise it results in a video level that is too high or too dim. 
2.  Confirm that the connecting cables are of high quality and properly 
inserted. 
3.  Check level controls located on your source input device or output display. 
Noise bars are "rolling" 
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. This difference is 
compensated by passing that voltage difference through any available 
interconnection, including your cables. 
WARNING! 
Do not disconnect the ground from any 
piece of 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 interconnecting cables and reconnect them one at a time 
until the ground loop reappears. Disconnect the affected cable and replace, 
or insert an isolation transformer in the signal path. 
4.  Use a video Isolator, such as Kramer OC-1N or a differential amplifier 
such as Kramer 123V inserted in the video signal path. 










