Filter
Top Products
P300H P300 Series Modem Installation and Operating Handbook Page 110
Tx/BUC: 1:DC Supply[On] 2:10M Ref[Off]
3:Current Monitor[2400 - 2800mA]
Change, BUC/LNB, Tx/BUC, DC & References Menu
TERMINAL The Modem takes control of the BUC to act as an integrated terminal, and the two
together respond as follows:
The modem IF output level screens are replaced by a screen allowing the
operator to set the output power at the BUC flange.
The Modem continuously reads the monitored power output from the BUC,
and automatically varies the modem IF level and BUC attenuator to maintain
the set power at the BUC flange (ie compensates for temperature changes
in cable, equipment etc).
The BUC Tx On/Off output is maintained as `On` (the Tx carrier can still be
muted on Change, Tx, Modulator, Carrier menu).
The modem automatically reads the frequency shift from the BUC, and
configures the modem for display / entry of the final SHF frequencies instead
of IF frequencies.
Terminal mode can only be used with a single carrier through the BUC, as the
modem will try and compensate for the combined measured power by adjusting
the single carrier from the modem controlling the BUC.
Terminal mode, where the Tx power is varied to maintain a steady level at the
BUC flange, is NOT compatible with AUPC which requires the Tx power to vary
to meet receive criteria.
6.12.3 Change, BUC/LNB, Tx/BUC, DC & REFERENCES Menu
This screen is only available on P310 L-Band modems where the BUC Type has been set to other than
None
DC SUPPLY If fitted with the P315 BUC DC supply option, then the modem may source 100W
of 24V or 48V (factory option) to the BUC `up the coax` or `line powered`. The
only option available here is On or Off.
CAUTION: Needless to say severe damage may occur if a DC supply is fed to a
BUC not configured for being `Line powered`.
10M REF The internal 10MHz reference may similarly be sourced from the modem `up the
coax` to the BUC. The only option available here again is On or Off.
CURRENT
MONITOR If the modem is sourcing the DC supply to the BUC, then it may be set to monitor
the current drawn by the BUC, and to raise an alarm (Tx Fault) if it goes outside
a user defined window. Two subsequent screens allow the user to independently
set the low and high current alarm thresholds. The current being drawn by the
BUC can be monitored from the Monitor, BUC menu’s