LNB Change Guide
Here you can find information on how to change over a refurbished LNB unit.
Please do not publish this link to your customers as these files should only be handled by technicians because unwarranted use may damage the Oyster System.
In early 2008 Foxtel and Austar decided to change their local oscillator frequency from 10.6 GHz to 10.7 GHz. While there is a workaround for the Foxtel system, it is advisable to change the LNB on Oyster Digital Systems to a 10.7 GHz model if your client is watching either Foxtel or Austar.
ON THE ROOF:
Take the complete head unit off by removing the 2 bolts from the arm.
Carefully pull the wiring out of the arm until you see the heatshrunk connector of the yellow/red/black servo power supply.
Cut heatshrunk tube and mark positions before you pull connector apart…
… and take coax cable(s) off LNB. On a Twin Unit you will have to cut the heatshrink to unscrew 1 coax cable. The otherone can be unscrewed by turning the LNB unit rather than the screw. That saves you cutting and replacing the heatshrink.
IN THE WORKSHOP:
remove rubber capped nut and white cover.
Careful, when the nut is removed, bearing balls will start falling out of the housing through the screw hole.
Undo cover plates.
Your LNB should now look something like this.
Undo screw on top of the servo.
Remove white plastic cog.
Start turning LNB in circles with the screwhole pointing downwards until all bearing balls have fallen out.
You should now be able to pull the LNB from its housing.
Remove race from LNB neck by unscrewing 4 screws.
The 2 halves are taped to the LNB neck, ease them off the neck.
Put 2 strips of doublesided tape on new LNB, use old LNB as reference.
Tape bottom half to LNB neck with white plastic gears facing toward the LNB body, use old LNB for position reference.
Do the same with top half and screw together.
Insert LNB into housing…
…and start feeding bearing balls back into the races through screwhole. Less is is sometimes more. It is more inportant that the LNB turns freely than getting all balls back in. In later models, the manufacturer replaced some of the metal balls with smaller white plastic balls.
Make sure that LNB turns freely. You may have to use some of the smaller white plastic balls instead of all steel balls. Put rubber capped screw back into hole for now to prevent balls from falling out. Add high temperature grease if required.
Refit plastic cog to servo, make sure LNB has about equal travel from left to right (should be sitting at about 4 o’clock on the right and 8 o’clock on the left)
Refit cover plates.
Refit white plastic LNB cover.
Refit LNB housing to arm, take care not to reverse the servo connector. They are coded, but can be easily forced in the wrong way. Waterproof connectors with heatshrink or self amalgamating tape. Refit coax cable(s) to LNB and waterproof as above. Do a Firmware Upgrade