Specifications

TROUBLE SHOOTING.
To begin trouble shooting you must first identify the source of the
interference. First disconnect the suspected UPS and
turn it off (power it down).
This will guarantee that the UPS cannot create the interference in the first place.
Then reconnect the equipment that was powered by the UPS to a normal non
UPS power line. Check the monitor and see if the interference has been
eliminated. This test will check for direct camera power supply and ground loop
type interference at the same time.
If your interference did not go away and you suspect that another UPS
somewhere else in the building is operating, you can check for ground loop
interference by placing a battery operated monitor on the end of the coax cable at
the DVR end of the system. Observe the monitor. If the interference is gone, that
indicates ground loop interference. Confirm this by touching the original DVR
ground to the connector shield on your battery operated monitor while you are
watching the picture. Use a short wire or a coax jumper (shield only). If you touch
the ground to the monitor the interfering signal will re-appear if it is ground loop
induced interference.
HOW TO SOLVE THE PROBLEM.
If the interference is resolved by disconnecting the UPS then you should
replace the UPS with a sine-wave, semi-sine-wave or quasi-sine-wave type of
UPS. The best way is not to create the interfering signal in the first place. If the
interfering signal is getting in through a ground loop then isolate the cameras from
ground at the camera end. This may be more difficult when using common power
supplies however first try an isolated wall mount power supply on one camera to
test whether power supply isolation will resolve the problem.
VIDEO LINES OF DEFINITION.
Picture quality can be defined by many different parameters, but the most
important from an observed picture detail point of view is the LINES OF
DEFINITION as observed on a Monitor. The larger the "number of lines" that can
be distinguished, the
greater the detail in the picture. The number of Lines of
Definition actually has nothing to do with the number of horizontal lines that
comprise the picture. In fact, all CCTV cameras used in the United States create
exactly the same number of horizontal lines in the picture regardless of the Lines
of Definition that the camera can produce.
CCTV TRAINING MANUAL PAGE 21 OF 28