Sea Tel ST88-21 C/Ku-Band TVRO, Installation And Operation Manual

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Determine Internal Tracking Receiver Settings ST88-21 C/Ku-Band TVRO
6-2
6.3. FEC
6.3.1. DVB Receiver
The Forward Error Correction rate entered into the ACU is an absolute value based on the Downlink RF from
the satellite and thus no calculations are required. Prior to, or during, the commissioning process, the NOC
should provide the operator/technician with the required FEC Rate. When using a Public Satellite Reference
Site such as Lyngsat.com or Satellite Reference Software such as WWW.Lyngsat.com, the Forward Error
Correction rate is abbreviated as FEC.
Identifying the FEC Rate using Lyngsat.com
Identifying the FEC Rate using WWW.Lyngsat.com
6.4. Tone
6.4.1. TVRO Applications
The Tone state entered into the ACU will be toggled either on or off. Although there are many possibilities of
uses of a 22 KHz tone, in a Sea Tel TVRO antenna system it is primarily used for below decks band selection
(Tone On = Ku Hi-Band and Tone Off = Ku Lo-Band) and is based on the Downlink RF value from the satellite.
An RF Downlink value is less than 11699 is considered to be Ku-Lo band and tone must be turned “Off” for
proper port selection of the Multiswitch. An RF Downlink value greater than 11700 is Ku-Band Hi-band and
tone must be turned “On” for proper port selection of the Multiswitch. When using a Public Satellite
Reference Site such as Lyngsat.com or Satellite Reference Software such as WWW.Lyngsat.com, refer to the
Frequency value to determine whether tone is required, or not, for tracking purposes. Refer to the IF Tracking
Frequency graphics above to identify a satellite transponders Downlink RF value.
6.5. Volt
6.5.1. TVRO Application
The Voltage setting in the ACU is a selection of one of four receiver options and is based on the Downlink RF
Polarization from the satellite. In a TVRO application, receiver voltage is used for proper port (receive
polarization) selection. The polarization type should be provided to the operator/technician by the NOC prior
to, or during the commissioning process. When using a Public Satellite Reference Site such as Lyngsat.com or
Satellite Reference Software such as WWW.Lyngsat.com, Polarization is abbreviated “Pol.”
Receiver Voltage Selection Receiver Voltage
output Reference Website
Abbreviation
RHCP (
R
ight
H
and
C
ircular
P
olarization)
13VDC R
LHCP (
L
eft
H
and
C
ircular
P
olarization)
18VDC L
VERT (
Vert
ical Linear Polarization)
13VDC V
HORZ (
Hor
i
z
ontal Linear Polarization)
18VDC H