AP401FULL- HD_rev. 09_UK
22
NOTE:
As with any receiver, the presence of several high-level channels within
the reception band can generate spurious signals. If the operator does not use the
attenuator appropriately under these conditions, in the case of automatic
measurements, frequencies which are not actually occupied by channels could be
measured at an unexpected level.
4.8.
MEASURING THE OPTICAL POWER
In order to enable optical measurement mode, press the
OPT
button to configure the
instrument for its “SPECTRUM” function.
The optical measurement function can also be enabled in the following manner:
1.
Hold down the field strength meter’s
LNB
button for about 3 seconds. The relative
menu will appear on the display.
Select the “OPTICAL” menu item and then press
ENTER
. Turn the dial to select
ON
(or else
OFF
to disable the function) and press
ENTER
again.
When the optical measurement function is enabled, the
“Vcc”
indicator, which normally
appears on the field strength meter’s status bar to indicate the power supply voltage for an
LNB, will be replaced with
“optPOW-dBm”
. The value indicated below this item indicates
the optical power measurement.
The following indications will also appear on the instrument’s display:
1.
The optical window (wave length) in use will appear in the upper central portion of
the screen.
( 1310 nm, 1490 nm, 1550 nm).
The optical window to be used for the measurements can be selected in the following
manner:
⇒
Hold down the
LNB
button for about 3 seconds. The relative menu will appear
on the display.
⇒
Turn the dial to select the “Optical Menu” item and press
ENTER
to confirm the
selection.
⇒
Turn the dial to select the desired optical window and press
ENTER
to confirm
the selection.
⇒
Press the
LNB
button to exit the menu.
2.
OPT POW indication:
On this line, a blue bar proportional in length to the optical signal indicates the
relative power of the measured signal, thereby allowing for a satellite dish with
optical LNB to be properly positioned, for example.
3.
ref POW:
The optical power value indicated represents the reference level for the calculation of
optical power losses. In order to set the reference value, proceed in the following
manner:
⇒
Connect the primary source of the optical signal to be measured (LNB, head
amplifier, etc.). The field strength meter’s status bar will indicate the power of the
measured signal in dBm under the “optPOW” item.
⇒
Press the
2nd
and
Store (PR)
buttons in succession. The optical power value will be
stored and indicated under “refPOW”. This value represents the reference optical
power value for calculating losses.
