COBHAM Sea Tel 4010W-91, Installation Manual

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4010W-91 Installation Manual Functional Testing
15-2
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When used as simple “BLOCKED” logic output for a single Sea Tel antenna, this output could be used to light a
remote LED and/or sound a buzzer to alert someone that the antenna is blocked, and signal is lost.
•
In a “Dual Antenna” installation, this logic output(s) is used to control Dual Antenna Arbitrator panel of coax
switches to switch the source inputs to the matrix switch from Antenna “A” to Antenna “B”, and vice versa.
•
When used as simple “
RF Radiation Hazard
” logic output for a single Sea Tel TX/RX antenna, this output
could be used to suppress RF transmissions while the antenna is pointed where people would be harmed by
the transmitted microwave RF power output. The SW2 output would be interfaced to the satellite modem to
disable the TX output signal from the Satellite TXRX Modem whenever the antenna is within the RF
Radiation Hazard zone(s).
•
When used for “ FCC TX Mute ” logic output for a single Sea Tel TX/RX antenna, this output could be used to
suppress RF transmissions whenever the antenna is mis-pointed 0.5 degrees or more, is blocked, searching,
targeting or unwrapping. The SW2 output would be interfaced to the satellite modem to disable/mute the
TX output signal from the Satellite TX/RX Modem. When the mute condition is due to antenna mis-pointing,
it will not un-mute until the pointing error of the antenna is within 0.2 degrees. The default output is
contact closure to ground when the antenna is mis-pointed, therefore provides a
ground
to “Mute” the
satellite modem on the SW2 terminal of the Terminal Mounting Strip. If your satellite modem requires an
open
to “Mute”, refer to SYSTEM TYPE parameter 16 value to reverse the output logic from the ACU.
To Test the blockage function:
1. Press the NEXT key until you are at the Status menu. Press ENTER to access the Tracking menu.
2. Press the RIGHT arrow key to bring up and move the cursor to the far right. Press the UP arrow to simulate a
manual BLOCKED condition. BLOCKED will appear in the Tracking display.
3. Verify that SW2 terminal shorts to ground (or open circuit if you have SYSTEM TYPE configured to reverse
the output logic) and that the external alarms actuate OR the Dual Antenna Arbitrator coax switches toggle
(if antenna B is not blocked) OR the Satellite Modem TX is disabled/muted.
4. Press the LEFT arrow key and then press the UP arrow key to turn the simulated blocked condition OFF.
BLOCKED will disappear from the Tracking display.
5. Verify that SW2 terminal is open circuit (or ground if you have logic reversed) and that the external alarms
deactivate OR the Satellite Modem TX is un-muted. The Dual Antenna Arbitrator coax switches should not
toggle until you manually block Antenna B ACU.
15.5. Four Quadrant Test Tracking
A Four Quadrant Tracking Test is the best way to test tracking (regardless of which tracking mode is being used). This
tests each of the 4 quadrants (UP, DOWN, LEFT & RIGHT of peak signal AZ/EL pointing) to assure that the tracking
mode being used drives the dish back to peak satellite signal level.
Note:
Return to peak should take about the same
amount of time from each of the four quadrants.
1. Ensure tracking receiver parameters are set correctly and that system is on satellite with peak signal (AGC
above threshold).
2. Ensure tracking LED is off – If not press the
TRACK
key to toggle tracking off
3. Press the
NEXT
arrow key a few times until Antenna menu is displayed
4. Note the current Azimuth and AGC values.
5. Press and hold the
RIGHT
arrow key to drive Azimuth down until displayed AGC drops 100 counts
(approx. 2-3 dB) (Do not drive antenna so far that AGC falls below threshold)
6. Press the TRACK key to re-enable tracking.
7. Monitor the Azimuth and AGC Values for the next 20-30 seconds.
8. Verify the Azimuth and AGC return to the values noted in step 4.
9. Verify the amount of time it took for tracking to bring AGC back to peak is within the specifications
** Nominal time to get back to peak is 8-30 seconds You should also be able to observe the DishScan tracking
decisions being carried out by ACU by viewing either a 2, 4, 6, or 8 in the bottom left-hand side of the
Azimuth Sub-menu display screen. A normal displayed response would be opposite than that of the axis
driven, i.e. for an antenna driven up (CW) is azimuth you would expect to see a majority of 4’s being
displayed indicating DishScan senses signal strength higher down in azimuth, therefore sending the Azimuth
Down command to PCU.