7706LT
Extended L-Band RF Fiber Transmitter
Page - 18
Revision 1.1
6.1.6. Adjusting the AGC Target Level
The target output level to be maintained by the 7706LT when AGC mode is user adjustable.
Adjustment of this parameter allows optimal laser depth of modulation and CNR performance to be
achieved. A typical value is –20 to –10 dBm, but for optimal performance it is recommended that a
spectrum analyzer be connected at the receive side of the link while this value is adjusted to provide
the best CNR performance while not introducing distortion products which may appear as an increase
in the noise floor while increasing the target level, or as “spectrum skirts”. To set the AGC target level,
select the
CTRL
menu item in the first menu level, then use the toggle switch to display the
OUTL
option
and press the pushbutton to select it.
CTRL
0 to -50 dBm
AGC output signal target level (default –20
(dBm)
OUTL
0 to -50 dBm
Note that this menu item is only applicable and visible when the card is set to
operate in AGC mode.
6.1.7. Setting the Passcode (DWDM versions only)
Due to the high-powered lasers used on the DWDM version of these cards, it is possible to turn the
laser on and off and protect this function with a passcode. This provides added optical safety. Depress
the pushbutton and select the PSWD option. Actuate the toggle switch to achieve the correct code
number (Factory Default Passcode = 0000).
CTRL
PWSD
Store a new passcode (0-9999) required for
BLOCK configuration. This menu is not
available without entering the correct
passcode.
LASR+
Enable / Disable Laser. Only visible for
DWDM versions.
PSWD
0-9999
PSWL+
LASR+
0000-9999
ON
OFF
6.1.8. Setting the LNB Voltage Level
The voltage level for LNB power is user adjustable. To set the LNB output voltage level, select the
CTRL
menu item in the first menu level, then use the toggle switch to display the
LNBV
option
and
press the pushbutton to select it.
CTRL
18V
Sets the LNB output voltage to 18V.
13V
Sets the LNB output voltage to 13V.
OFF
Disables the LNB output voltage.
LNBV
18V
13V
OFF
