iDirect evolution e8350 - Peaking the Antenna

62 iDirect Satellite Router Installation and Commissioning Guide
iDX Release 3.3
Peaking the Antenna
known as Pulse Width Modulation (PWM). Pulses of differing duration are detected as
different voltages by a DC voltmeter.
Ta b l e 6 depicts the range of the PWM voltage output and the as
sociated signal status. When
peaking, the antenna is adjusted for maximum DC voltage
as indicated by a DC voltmeter.
A reading of less than 2 Volts indicates that the signal level is below the detection threshold
of the Satellite R
outer. When a signal at the correct frequency is detected, the PWM voltage
increases sharply to between 2 and 10 Volts. After downstream carrier lock is achieved, the
PWM voltage switches into the 12 to 20 Volt range. PWM voltages in this range increase
linearly with increasing signal strength.
Note: A reading of 12 Volts or greater cannot be obt
a
ined unless the Satellite Router
is locked to the correct spacecraft and network.
When power is applied to the Satellite Ro
uter, BUC power is available on the TX Out port
immediately after power-on self-test (POST) has completed. To disable the BUC supply and
enable the PWM output, follow the steps in “Peaking the Antenna” below.
11.3.2 Graphic Display
The Web iSite Antenna Pointing screen provides a graphic representation of received signal
strength over time. It provides a voltage amplitude display similar to an oscilloscope,
displaying a color-coded bar graph corresponding to the three voltage ranges shown in Ta b l e
6. The display is enabled when A
n
tenna Pointing is selected on the Commissioning screen.
Both the PWM voltage and the graphic display are used to peak the antenna.
11.4 Peaking the Antenna
Execute the procedures in the following sections to achieve peak received signal strength of
the downstream link.
To Peak The Antenna
1. Be certain that th
e antenna is pointed off the marked heading by at least 20 degrees in
azimuth.
2. In the navigation bar at the top of the W
eb iSite window, click the Commissioning button.
3. Click Antenna P
ointing (at left) to view the Antenna Pointing page. The graphic display
appears and begins to scroll across the screen.
4. For dual-receiver models such as the X7, select Rx1 or
Rx2 at upper-right. See Figure 40.
Table 6. PWM Voltage Ranges and Signal Status
Volts DC Signal Status
0 - 2 Not in pointing mode, hardware problem, or off satellite
2 - 10 Detecting RF energy, but not locked
on the downstream carrier
12 - 20 Locked on the downstream carrier