BK Precision 1249B, Instruction Manual

Page: 22 / 41

22
OPERATING INSTRUCTIONS
WARNING
To prevent electrical shock, observe the
precautions listed in the TEST
INSTRUMENT SAFETY section, located on
the inside front cover of this manual.
PRECAUTION AND TIPS
1. The most commonly encountered hazard in the use of this
instrument is “hot chassis” equipment. Always connect an
isolation transformer (such as the
B & K Precision Model
TR-110 or 1604 Isolation Transformer or Model 1653A or
1655A AC Power Supply) between the wall outlet and any
“hot chassis” equipment under test. See the TEST
INSTRUMENT SAFETY section, steps 7 and 8 for more
information
2.
The RF/IF and COMPOSITE VIDEO outputs of this
NTSC Generator are rated to withstand voltages of -35 to
+35 volts. All other outputs are rated to withstand -5 to +5
volts. The NTSC Generator must only be connected to
circuit points where the dc + ac peak voltage is within the
specified limit (±35 volts for the
RF/IF and COMPOSITE
VIDEO outputs and ±5 volts for all other outputs). If in
doubt, make a voltage measurement first. Also take care to
prevent accidental contact with high voltage points.
3. All outputs have a source impedance of 75
Ω.
Therefore,
75
Ω
coaxial cable RG-59/U) is recommended for
interconnecting cables.
FAMILIARIZATION
To familiarize yourself with the operating controls, capabilities
and operating characteristics of the NTSC Generator, we
recommend that you connect it to a color television receiver
that is in proper operating condition and observe all the
patterns. An oscilloscope or waveform monitor may also be
used to observe all the waveforms produced.
INITIAL SET-UP
1.
Connect the power cord of the NTSC Generator to a
120VAC, 60Hz outlet
2. Turn on the instrument by setting the POWER switch to
the ON position (engaged). The POWER indicator will
light when the power is on.
3. Apply power to the equipment under test and turn it on.
For “hot chassis” equipment, use an isolation transformer.