KRAMER ELECTRONICS LTD.
9
9.
TAKING CARE of YOUR SWITCHER/SCANNER
Do not locate your switcher/scanner in an environment where it is susceptible to dust or moisture. Both of these
may damage the electronics, and cause erratic operation or failure. Do not locate your switcher where
temperature and humidity may be excessive. Doing so may also damage the electronics, and cause erratic
operation or failure of your switcher. Do not clean your switcher/scanner with abrasives or strong cleaners.
Doing so may remove or damage the finish, or may allow moisture to build up. Take care not to allow dust or
particles to build up inside unused or open connectors.
10.
TROUBLESHOOTING
NOTES
1. Please note that if the output signal is disturbed or interrupted by
very strong external electromagnetic interference, it should
return and stabilize when such interference ends. If not, turn the
acceptor/source power switch off and on again to reset the
machine.
2. If the following recommended actions still do not result in
satisfactory operation, please consult your KRAMER Dealer.
10.1
Video and other High Frequency Signals
Problem Remedy
No signal at the output
device, regardless of
input selected.
1. Confirm that your sources and output device are powered on and connected
properly.
2. Confirm that any other devices in the signal path have the proper input and/or
output selected.
3. Use a Video Tester to test the video path leading to/from your switcher (see
section 4.1 " Video Tester")
Signal level is too high
or too dim.
1. Verify that the signal line is well matched through 75ohm impedance; otherwise
it results in a signal level that is too high or too dim.
2. Confirm that the connecting cables are of high quality, properly built and
terminated with 75ohm BNC connectors. Check level controls located on your
source input device or output display or recorder.
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. This difference is compensated
by passing that voltage difference through any available interconnection, including
your video cables.
WARNING!
DO NOT DISCONNECT THE GROUND FROM ANY PIECE OF VIDEO
EQUIPMENT IN YOUR SIGNAL PATH!
Check the following to remove hum bars:
3. Confirm that all interconnected equipment is connected to the same
phase of power, if possible.
4. Remove equipment connected to that phase that may introduce noise,
such as motors, generators, etc.
5. Disconnect all interconnect cables and reconnect them one at a time until
ground loop reappears.
6. Disconnect the affected cable and replace, or insert an isolation
transformer in the signal path.
