no color?
Turn off the Line-Lock
feature of any video source connected to this
equipment.
Most likely, any loss of color is because your video signal source does not
conform to Electronic Industry Association (EIA) requirements.
Colorado Video equipment requires video input signals that conform to EIA
RS-170A and NTSC specifications. These industry standard specifications
require that color subcarrier frequency be 3,579,545+10 Hz, horizontal sync
frequency be 15,734.263 Hz, and vertical sync frequency be 59.94 Hz. Video
equipment must strictly adhere to these frequencies in order to maintain proper
phase relationships between these three signals.
Cameras operating in Line-Lock mode violate these standards by synchronizing
vertical sync to the 60 Hz (not 59.94 Hz) sine wave from the power line. To
maintain proper phasing between horizontal and vertical sync, these cameras
further have to violate the horizontal frequency specification by running at
15,750 Hz, not 15,734 Hz.
Colorado Video equipment runs at the horizontal and vertical sync frequencies
present at its input. In order to maintain industry mandated phase relationships
between vertical, horizontal, and color subcarrier, the subcarrier frequency may
be forced too high for some monitors to display color. Many times in this
situation, some monitors will display color while others will not.
To set your camera for proper operatio
n, find a switch or jumper on the
camera that refers to “line-lock” (sometimes “line-loc”) or “external” and
switch it away from that position. Proper settings are referred to as “int”,
“internal”, “internal crystal” or line-lock “off”. If this setting is not available,
you can install a Time Base Corrector in series between the camera output and
Colorado Video input. It is also possible that running your camera on a power
adapter with a DC, not AC, output will solve the problem. It may be necessary
to try both polarities when using a DC adapter.
PAL
Users: The frequencies are different but the same principle applies.
