Installation – 5
Fig. 4.VLM-40 display for standard
EIA (split-field) color bar signal
with standard setup at 140 IRE
(1 V p-p).
VLM-40 NTSC T
ECHNICAL
I
NSTRUCTION
M
ANUAL
INSTALLATION
2. After mounting or placing the unit, plug the ac cord into
the ac receptacle and observe that the meter display on the
front panel becomes backlit.
NOTE: If backlighting is off, check your ac line for power, or test
the internal 0.5 A fuse for continuity (see Schematics).
3. Connect a 75-ohm video cable from a standard television
signal test generator to either video (BNC) connector on the
back panel. Select Term. or Hi-Z to terminate the connection.
4. Feed a standard EIA split-field color bar signal with standard
setup at 140 IRE (1 V p-p) to the VLM-40 and verify that the
meter matches the reading shown in Fig. 4.
NOTE: The VLM-40 is calibrated at the factory for standard
video level of 1 V p-p. If your “house standard” is different
value, use the video Gain potentiometer (see Fig. 2). This control
will provide an adjustment range that accommodates signals
down to 0.5 V p-p.
5. After completing steps 1 through 4 above, proceed to the
Operation
chapter to learn how to read the VLM-40 meter.
COMPOSITE VIDEO LUMINANCE METER
MODEL VLM-40
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-40
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20
40
60
80
100
120
© 1990
SYNC
LUMINANCE
IRE UNITS
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SYNC
SETUP
