Home Satellite TV Antenna
(160-2508)         Feed Boom, Feedhorn, and LNB       Faxback Doc. # 31425

You must mount the feedhorn and LNB, which collect and amplify the
satellite signals, at the end of the feedboom.  The feedboom is specially
designed to position the feedhorn exactly at the focal point of the dish.
The focal point is the spot where the dish concentrates the signals it
receives from a satellite.

The feedboom also positions the feedhorn in the correct horizontal/vertical
axis, in relation to the satellite signals.

For this procedure you need:

*  Feedhorn and Feedhorn Hardware (in a separate box)

*  LNB (in a separate box)

*  Feedboom (System Box #1)

*  Shroud Brackets and Hardware (System Box #2)

CONNECTING THE LNB TO THE FEEDHORN

Connect the LNB to the feedhorn as follows:

1.  Place the rubber gasket (from the feedhorn box) in the groove on the
    open face of the LNB.

    NOTE:  If necessary, trim excess rubber from the gasket to make it
           fit the groove.

2.  Press the face of the LNB against the feedhorn's LNB bracket.  Be
    sure the rubber gasket stays in place.

3.  Using the nuts and bolts from the feedhorn box, secure the LNB to
    the feedhorn.

NOTE:  Use the three shorter bolts for the three pre-tapped holes in the
       feedhorn's LNB bracket.  Use the longer bolts and the nuts for all
       the other holes.

ATTACHING THE ELECTRONICS TO THE FEEDBOOM

When attaching the feedhorn and LNB to the feedboom, you must also attach
the shroud brackets that will hold the protective electronics shroud in
place.  These brackets and the necessary nuts and bolts are located in
System Box #2.

To attach the electronics to the feedboom, perform the following steps.

1.  Align the back of the feedhorn with the feedboom bracket, and mark the
    two holes in the feedhorn that are to be connected to the feedboom
    bracket.

    NOTE:  Be sure to align the holes in the feedhorn with the holes in
           the bracket.

2.  Attach two shroud brackets to the holes that are not used for the
    feedboom bracket.

    Align the brackets so they stick straight out from the feedhorn ring.

3.  Attach the feedhorn to the feedboom bracket with the remaining two
    shroud brackets between the feedhorn and the feedboom bracket.

ATTACHING THE INCLINOMETER

The inclinometer (inside the electronics shroud in System Box #3) helps
you align the dish and helps you locate your first two satellites.

1.  Insert the straight end of the feedboom through the inclinometer's
    plastic sleeve.  You can point the numbered scale toward either side
    of the dish, but the west side is usually best.

2.  Remove the indicator needle from the back of the inclinometer and
    insert it through the eyelet so that the needle points at the
    numbered scale.

3.  Slide the inclinometer up the feedboom so that it is about 1 foot from
    the end and temporarily tape it there.  This keeps the inclinometer out
    of the way during the next procedure.

INSERTING THE FEEDBOOM INTO THE MOUNT

1.  Back out the feedboom lock screw until it does not extend into the
    boom cylinder.

2.  Hold the feedboom with the straight end near the hole in the mount's
    round hub.

3.  Route the satellite cable through the straight end of the feedboom and
    out the end that holds the electronics.

    NOTE:  Put a little liquid detergent or spray lubricant inside the
           feedboom to make the cable slide more easily through the boom.

4.  Insert the straight end of the feedboom fully into the hole in the
    mount's round hub.

5.  Rotate the feedboom so that the hole in the boom aligns with the hole
    in the hub collar.  Then, insert the self-tapping screw (from the
    Electronics Shroud Hardware bag in System Box #2) to hold the feedboom
    in proper alignment.

6.  Behind the hub plate, tighten the feedboom lock bolt to further secure
    the feedboom.

7.  Connect one of the satellite cable's F-connectors to the matching
    terminal on the LNB, and slide the rubber weather boot over the
    connection.

    NOTES:  Use the hand crank to move the dish to the side so that the 
            electronics are easier to reach.

            You can use either F-connector, but make a note of the one you
            use (the one at the edge of the cable or the one inside the
            cable).  This will be important when you connect the cable to
            the satellite receiver.

8.  Slide the weather boot over the unused F-connector.

    NOTE:  You can use the second coaxial cable to upgrade your system for
           dual C-band or C/Ku-Band operation.  Or, you can use it as a
           spare if something goes wrong with the first.

9.  Twist together the satellite cable's red, white, and black wires with
    the corresponding wires coming from the feedhorn's polarity-control
    motor and secure the twisted wires with the supplied wire nuts.  Then,
    wrap the connections with plastic tape.

10. Remove the tape from the inclinometer so that it rests against the hub
    collar and swings freely around the feedboom.

    Note:  Leave enough extra cable between the boom and LNB to make 
    connections or disconnections convenient, but pull excess cable back
    through the boom, mount, and post.


(CS 3/18/96)