Sea Tel 9797A-27, Инструкция по установке и эксплуатации

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Setup 9797A-27 C-Band TXRX
5-4
To enter the calculated HFO value, press Antenna Control Unit MODE key repeatedly, enter the password
ant the REMOTE AUX menu and then continue pressing the MODE key until you have selected the
REMOTE COMMAND window.
In the REMOTE COMMAND window, key in " .78” and hit the ENTER key. "N0000" should appear in the
command window. Key in 6 and the three digit HFO value from 000 to 255 (corresponding to 0 to 360
degrees) that you calculated above. Press ENTER to send the HFO value command to the PCU. Press
ENTER several times to select the REMOTE PARAMETERS display. Press the UP arrow key and then
press the ENTER to save the HFO value in the PCUs NVRAM.
If you want to find out what the current HFO value is key in 6 999 and hit ENTER.
EXAMPLE: In the “Antenna stopped before the Bow” example above, the HFO calculated was 222. To
enter this value:
1
Key in " 6222 " to set HFO to 222. The display should now show "N0222".
2
Press ENTER to send this HFO to the PCU.
3
Press ENTER (or MODE) several times to select REMOTE PARAMETERS . Press UP arrow
and then ENTER to save the HFO to NVRAM in the PCU.
4
Press ANTENNA twice , and manually drive the antenna toward the Home Switch (or re-
Initialize the antenna). The Home Switch must actuate to preset the counter to the new value
before you target the satellite again! Now, whenever the Home Switch is actuated, the new
value of HFO (the actual Relative position of the antenna) will be loaded into the Relative
counter.
5
If there was previously a positive or negative value of AZ TRIM, set it to zero and SAVE NEW
PARAMETERS.
6
Follow the Optimizing Targeting procedure to re-evaluate small corrections in EL TRIM and AZ
TRIM and verify that you can repeatedly target a desired satellite (/- 1 degree, or less).
If your antenna is periodically blocked by some part of the ships structure, you may want to refer to the
Radiation Hazard and Blockage Mapping section below.
5.5. Radiation Hazard and Blockage Mapping
The ACU can be programmed with relative azimuth sectors (zones) where blockage exists or where transmit
power would endanger personnel who are frequently in that area.
The lower and upper limits are user programmable and are stored in NVRAM within the ACU parameter list.
When the AZ LIMIT parameters are set to create these
ZONES several things happen when the antenna is
within one of the zones:
1
Tracking and auto Search are suspended whenever the antenna is pointed within one of the zones.
2
“BLOCKED” will be displayed in the TRACKING window.
3
A contact closure to ground is provided on the SW1 terminal (J3-11) on the Terminal Mounting Strip.
This Switch output provides a “Blocked” or “RF Radiation Hazard” logic output.
While the antenna is pointed within the zone it will follow its azimuth sensor output, and the heading input, to
keep the antenna accurately pointed in azimuth and at the same elevation it was at when the signal was lost.
Tracking is suspended to prevent the antenna position from wandering off prime pointing due to noise when
the signal from the satellite is blocked. When the antenna exits the zone it will be on satellite, tracking will re-
peak the signal and the SW1 contact closure will open.
The ACU provides a contact closure to ground on the SW1 terminal (J3-11) on the Terminal Mounting Strip
when the antenna is pointed within any one of the blockage/hazard zones or the system is searching,
targeting or unwrapping. The contact closure is a transistor switch with a current sinking capability of 1 Amp.
Pressing the 5 key when the TRACKING window is selected can
simulate a manual BLOCKED condition to
test SW1 logic output.