Sea Tel 9497B-21, Installation And Operation Manual

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Functional Testing 9497B-21 C/Ku-Band TVRO
6-2
4. Note the current peak AGC value. Press the
Tracking
key to toggle Tracking OFF, press the
DOWN
arrow
key repeatedly to move the antenna down in elevation until AGC falls about 100 counts. Turn Tracking ON
and verify that the antenna moves back up in elevation and that the AGC rises to its’ previous high value.
5. Note the current peak AGC value. Press the
Tracking
key to toggle Tracking OFF, press the
RIGHT
arrow key
repeatedly to move the antenna up in azimuth until AGC falls about 100 counts. Turn Tracking ON and verify
that the antenna moves back down in azimuth and that the AGC rises to its’ previous high value.
6. Note the current peak AGC value. Press the
Tracking
key to toggle Tracking OFF, press the
LEFT
arrow key
repeatedly to move the antenna down in azimuth until AGC falls about 100 counts. Turn Tracking ON and
verify that the antenna moves back up in azimuth and that the AGC rises to its’ previous high value.
6.6. Blockage Simulation Test
Blockage output function is used to modify the behavior of Tracking and Searching when there is a known blockage
zone. The ACU provides a contact closure to ground on the SW2 terminal of the Terminal Mounting Strip when the
antenna is pointed within any one of the blockage/hazard zones or the system is searching, targeting, unwrapping or is
mis-pointed by 0.5 degrees or more (FCC TX Mute function for Transmit/Receive systems only). The contact closure
is a transistor switch with a current sinking capability of 0.5 Amp. This logic output control signal is used for:
•
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.