23
OPERATING INSTRUCTIONS (CONT.)
4.
RF Output
The rf output of the NTSC Generator may be applied to a television
receiver, video tape recorder or other video equipment tunable to
channel 3 or 4. Use the following procedure:
a.
Connect a coaxial cable from the
IF/RF
output jack of the
NTSC Generator to the antenna terminals. The 75
Ω input
point is desired, or use 75
Ω to 300Ω coupler.
b.
Set the
RF/IF
switch on the Generator to the
RF
position
(disengaged).
c.
Set the channel selector of the equipment under test to channel
3 or channel 4, whichever is not used for broadcasting in your
area.
d.
Set the
CH 4/CH 3
switch on the NTSC Generator to the
same channel that was selected on the equipment under test.
e.
Patterns may now be selected.
5.
I-F Output
The i-f output of the NTSC Generator may be injected into the i-f
section of television receivers, video tape recorders, or any other
video product using the standard 45.75MHz i-f frequency. Use the
following procedure:
a.
Connect a probe to the
IF/RF
output jack of the NTSC
Generator.
b.
Set the
RF/IF
switch on the Generator to the
IF
position
(engaged).
c.
The probe may be used to inject the 45.75MHz i-f
signal at the desired point.
d.
Patterns may now be selected.
6.
Composite Video Output
A composite video signal may be applied to the input
or injected at subsequent test points of non-rf
equipment such as video monitors, video distribution
amplifiers, signal processing equipment, etc. A
composite video signal may also be injected into
circuit points after the video detector in television
receivers, video tape recorders, or other rf equipment.
The
IF/RF
and
COMPOSITE VIDEO
output jacks
may be used simultaneously if desired. Use the
following procedure:
a.
Connect a coaxial cable or probe from the
COMPOSITE VIDEO
jack of the Generator to
the desired point in the equipment under test.
b.
Adjust the
COMPOSITE VIDEO LEVEL
control to obtain the desired signal level and sync
polarity at the output jack. Fully counterclockwise
rotation gives maximum amplitude with negative
polarity sync. Clockwise rotation reduces level
and the center of rotation is minimum level.
Rotation past the center reverses the polarity of the
signal to positive sync and further clockwise
rotation increases signal level. Maximum
clockwise rotation is approximately 1Vp-p level,
although it is uncalibrated.
Summary of Contents for 1249B
Page 1: ...INSTRUCTION MANUAL Model 1249B NTSC GENERATOR ...
Page 16: ...16 THE NTSC COLOR VIDEO SIGNAL CONT Fig 3 Elements of Color Television Signal ...
Page 20: ...20 CONTROLS AND INDICATORS CONT Fig 4 Controls and Indicators ...
Page 35: ...35 MAINTENANCE CONT R7 Fig 8 Adjustment and Test Point Locations ...
