Comtech EF Data MBT-5000 - Manual (Page 95)

MBT-5000 L-Band Up/Down Converter System MN-MBT5000
Ethernet-based Remote Product Management Revision 4
6–17
Any LNA current reading that is outside the window may generate an alarm, a fault, or may be
masked entirely depending on the state of the user configured fault mask (see the MSK command
syntax in Chapter 7. SERIAL-BASED REMOTE PRODUCT MANAGEMENT for more information).
For example: If the LNA draws 100mA, and the LNB current fault window is set to the default
value of 30 (%), then the allowable current draw for the LNA will be from 70 mA minimum to 130
mA maximum because the window is +/- 30% centered on the calibrated LNA current draw.
• LNA Current Window: Use the drop-down list to select this feature as Enabled or Disabled.
• Low Power Threshold (dBm): Use this field to set the threshold value, in dBm, for the low
forward power alarm/fault. If the forward power drops below the specified value, the
alarm/fault will be indicated if the forward power monitor is set to Alarm or Fault instead of
the factory default of Mask.
Setting this parameter to the default value of 00.00 effectively disables the threshold.
Click [Submit] to save.
Calibrate LNA Current
You should calibrate the optionally installed LNA only when it is running at nominal
operating conditions.
This page provides the value of the LNA Current Supply (in mA) as a reference point. The LNA
current alarm upper and lower thresholds are determined by this calibrated LNA reference point
and the LNA current window setting.
Click [Calibrate Converter X] (where ‘X’ designates Converter A or Converter B) to perform an LNA
calibration and display the updated read-only value.