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Paradise P300 User Manual

Page 109

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P300H

P300 Series Modem Installation and Operating Handbook

Page 109

BUC Attached:[?] 1=None 2=Other 3=Std Ku 4=Ext Ku

5=Std C 6=INSAT C 7=PALAPA C

Change, BUC/LNB, Tx/BUC, BUC Type Menu 1

Modem/BUC control mode: [?]

1=Independent 2=Terminal (Closed Loop)

Change, BUC/LNB, Tx/BUC, BUC Type Menu 2

6.12.2 Change, BUC/LNB, Tx/BUC, BUC TYPE Menu

This screen is only available on P310 L-Band modems.

Options other than

None

or

Other

are only displayed if the FSK communications option is present within

the P310, and refer to standard Paradise BUC’s (with which the modem can communicate by FSK). If you
are using a non Paradise BUC, then please select

Other

and manually configure the BUC parameters.

The table below specifies the parameters for the listed BUC types:

BUC Type

Lower Frequency Limit

Upper Frequency Limit

Frequency Shift

None

Modem IF +/- limits around user set SHF Frequency Shift

Other

Modem IF +/- limits around user set SHF Frequency Shift

Std Ku

14.000 GHz

14.500 GHz

13050 MHz

Ext Ku

13.750 GHz

14.250 GHz

12800 MHz

Std C

5.800 GHz

6.4250 GHz

4900 MHz

INSAT C

6.725 GHz

7.025 GHz

5775 MHz

PALAPA C

6.425 GHz

6.725 GHz

5475 MHz

The difference between

None

and

Other

is that with

Other

the operator can configure the modem to

supply a 10MHz reference and a DC PSU to the BUC (if the internal BUC PSU option is fitted). With

None

,

these options are not available.

If a Paradise BUC is fitted then the following screen is displayed:

INDEPENDENT

The modem and BUC are both manually controlled from the modem front panel
(the modem as normal, and the BUC with

Change

,

BUC/LNB

,

Tx/BUC

). The

operator maintains control of the BUC Tx on/off status, and any BUC attenuator
available. The modem does however automatically report the IF frequency to the
BUC so the BUC may select the correct power calibration table for the monitored
power reported back to the modem, viewable under

Monitor

,

BUC

.

It is advisable to keep the BUC attenuator at maximum attenuation to avoid
overdriving the BUC input stages, unless there is considerable cross site cable
loss. Fine (0.1dB power control is done with the modem (

Change

,

Tx

,

Mod

,

Power

), whereas the BUC attenuator provides 1dB adjustment steps. If the

desired carrier power cannot be achieved with maximum BUC attenuation, then
there must be considerable cross site loss and so it is safe to reduce the BUC
attenuation. It is advisable to keep the modem carrier power several dB away
from either the upper or lower modem power end stop, to provide future fine
adjustment range.

Initial power adjustments must be made `off satellite`. The measured BUC power
can be viewed using

Monitor

,

BUC

.