1253 B&K Precision, 1253 Datasheet - Page 6

• Manufacturer Part Number: 1253
• Description: GENERATOR HANDHELD HDTV PATTERN
• Manufacturer: B&K Precision
• Type: NTSC Handheldr

Specifications of 1253

• Patterns: ANSI, Bar, Checker, Crosshatch, Focus, Multiburst, Needle, PLUGE, Raster, Staircase, Window
• Connection Method: BNC, S-Video
• Power Source: 9V Battery
• Equipment Type: NTSC Color Generator
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Connecting the unit
There are 3 BNC connectors on the top of the unit, labeled Y, Pb and Pr.
These are HDTV-Component video connections to be connected to the Y, Pb and Pr connectors of a
HDTV monitor or TV with component video input. There is also a DIN connector, labeled S-VID. This is
a S-Video (S-VHS) video connector to be connected to a TV with a S-VID input.
S-Vid Y
Pb
Pr
TOP
Pr
Pb
Y
S-VID
Facing Connectors
Top (Button) Side
The Y is the luminance signal, and Pb and Pr are the chrominance (color) signals. These BNC connectors
should be connected to BNC cables with a characteristic impedance of 75 (or 50) ohms. Some TVs use
RCA connectors, so a BNC-to-RCA adaptor could be used at the end of each cable.
According to the standards, the Y signal will drive a 1V peak-to-peak signal into a 75-ohm load, and the
Pb and Pr signals will drive 0.7V peak-to-peak signals into 75-ohm loads. The unit is correctly back-
terminated with 75 ohm impedance for each connector.
The Y signal can be used alone in some cases, to test using luminance only of an NTSC, PAL or SECAM
TV using its Composite input. The signal will be seen as a monochrome image, which is fine for most
patterns which are monochrome.
The S-VID may be used to test most non-HDTV monitors, which may have a S-Video input. This
connection provides no chrominance, so 3 color patterns (SMPTE Bars, Color Bars, and Raster) will
display only luminance and no color. The other 11 patterns will display normally.
The outputs of the unit have independent buffers so incorrectly loading an output will not affect the other
outputs. The outputs are also designed to drive short-circuit loads under abnormal conditions.
Power Supply
The unit is powered from an internal 9V battery.
A 9V Alkaline battery (e.g. Eveready Energizer 522) is recommended.
The unit is low power, and it should work under most normal operating conditions. There is a thermal
shutdown, as well are reverse protection function in the internal power supply circuitry for safety.
Low Battery Alarm
When the battery is low, a long beeping sound will be heard when the unit is switched on. You will need
to replace the battery soon after this. There will be a few hours of battery life left when you first hear this,
so this is a warning alarm, so be sure to replace the battery. If the unit is used for a few hours after this,
the battery will become depleted, and the unit will cease to function.