How to check an lnb

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The low noise blocker (LNB) on your digital satellite dish is the "eyes" at the end of the arm that extends out from the dish. The LNB pulls in the signal coming from the satellites and sends the information to the receiver that is hooked up to your television. If the LNB is not retrieving the information correctly then your satellite system is not getting the right information. Follow these steps to check your LNB to make sure it is working properly.

Check the signal strength of your satellite dish by going into the "Dish pointing" option in the receiver's menu and selecting "Signal strength meter". If the signal strength is strong enough, then the LNB is working and the problem is somewhere else in your system.

Inspect all the cables that run off the LNB and make sure they are not damaged. The LNB receives power from the receiver through the coaxial cable, and if the cable run is longer then 100 feet, using the standard RG6 coaxial cable is not recommended.

Confirm that the cable coming from the satellite is connected to the "Sat In" on the back of the receiver and not the "Antenna In".

Remove the LNB from the LNB arm on the satellite dish by unfastening the screws on the bottom of the LNB bracket and carefully sliding the LNB off the arm. There will be coaxial cables connected to the LNB, so be careful not to pull them off the unit.

Check the coaxial cables connected to the LNB and confirm they are connected securely to the jacks on the LNB. Twist the ends of the cables connected to the LNB clockwise to make sure they are tight.

Push an extra coaxial cable through the arm extending from the dish, starting from the bottom of the arm and continue until the cable comes out of the other end. The coaxial cable does not need to be more than six feet long. This cable will be used to test the signal.

Remove one of the cables connected to the LNB by twisting the end of the cable counterclockwise until it comes off. Replace that cable with the cable you just ran through the arm. Carefully slide the LNB back onto the arm. Do not insert the screws into the bracket at this point. Connect the other end of the cable to the input on a portable signal strength meter.

Check the signal strength on the meter at the dish. If you are not getting a reading, move the dish up or down two degrees and recheck the signal. Do this in both directions until you receive a signal. If you never get a signal then your LNB is bad.

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