Magni AVM-510A Series, Руководство оператора

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AVM-510A Option T (For Transmission Monitoring)
11-2
The AVM-510A-T senses the measurement signal on the selected line as indicated by the FIELD and
LINE designation at the top of the transmitter set. If the correct signal (FCC COMPOSITE or NTS7
COMPOSITE for NTSC or PAL CCIR 17/330 or NATIONAL ITS) is not present, the zero carrier
will also not be detected.
There are two ways you can designate the line number for the zero carrier reference pulse:
•
Manually set which line the AVM-510A-T uses
•
Enable the AVM-510A-T to search lines 9 through 25 for the reference pulse
To do so:
1. Press the Mesmnt button.
2. Select ZERO CARRIER and then press the Entr button (see Figure 11-2).
3. Select LINE: and then press the Entr button or turn the knob to choose between SCAN and
FIXED.
4. If you select FIXED, select FIXED LINE SELECT: and then turn the knob to choose the line
where the pulse is located.
5. Press the Clr Mnu button exit.
If you choose SCAN, the AVM-510A immediately begins to scan lines 9 through 25 (in the selected
field) for a zero carrier reference pulse. Note that the Zero Carrier menu flickers as it scans to find the
pulse.
NOTE:
If the width of the zero carrier reference pulse is less than 20
µ
s, you should
operate in FIXED mode because the AVM-510A-T might not find a narrow reference
pulse. Consequently, the AVM-510A-T will continously scan forever.
If the AVM-510A-T does not find a reference pulse, or if the FIXED line you selected does not have a
reference pulse, the transmitter measurement set shows NO ZERO REFERENCE PULSE near the top
of the display.
Measure Line
Notice the selected field and line number at the very top of the automeasurement display. You can
designate the line and field of the signal to be monitored through the following menus:
1. Press the
Mesmnt
button.
2. Select SELECT SET and then press the
Entr
button.
3. Select TRANSMITTER and then press the
Entr
button.
4. Select MEASURE LINE.
5. Turn the knob to choose the line.
6. Press the
Field Select
button to switch fields or turn the knob through one field and then into the
next.
The alternate method is to press the
Line Select
button (when you are in TRANSMITTER SET),
turn the knob to set the line, and then press the
Field Select
button to set the field.