Parts of a Satellite Dish – Labeled Dish, LNB and Mount

All 11 parts on the diagram

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The dish and its mount 8

Reflector (dish) Its curve is part of a parabola. It reflects the weak signal from the satellite to one spot in front of it, the focal point.
Feedhorn It gathers the signal the dish reflects onto it. It sits at the focal point. On home dishes it is built into the LNB. The pair is called an LNBF.
LNB (low-noise block) Short for low-noise block downconverter. It amplifies the signal and shifts it to lower frequencies that can travel down a cable to the receiver indoors.
LNB arm (feed arm) It holds the LNB at the focal point. That is in front of the dish. The cable is threaded through it.
Elevation scale Elevation is the up-and-down angle of the dish. The bracket is tilted until its edge lines up with the right angle on this scale, then the bolts are tightened.
Mast clamp It grips the mast. With its bolts loose the dish can swing from side to side, which sets the direction it faces, the azimuth.
Mast Its top part has to be exactly upright. Otherwise the dish cannot be aimed accurately.
Coaxial cable It carries the signal from the LNB to the receiver. It also carries power from the receiver up to the LNB.

At the house 3

Grounding block The cable from the dish connects to one side. The cable to the receiver connects to the other. It is mounted close to where the cable enters the house.
Ground wire It joins the grounding block to the building's ground. Grounding helps protect the system from lightning damage.
Receiver The cable from the dish ends here, near the television. The receiver decodes the chosen program for the television to show.

How this list was compiled: Every name checked on 2026-09-30, a name kept only where two independent sources use it. (1) Wikipedia, text only: Satellite dish (parabolic dish, focal point, feedhorn, LNB, LNBF, coaxial cable to the receiver), Low-noise block downconverter (feed arms in front of the dish reflector, cable to the receiver inside the building), Feed horn, Offset dish antenna and Satellite television. (2) How Products Are Made, Satellite Dish, http://www.madehow.com/Volume-1/Satellite-Dish.html (parabolic reflector, feed horn, coaxial cables to the receiver in the house). (3) Three unrelated installation guides, read as full text on the Internet Archive: a satellite television installation guide, https://archive.org/details/manualzz-id-835341 (reflector, LNBF, LNBF arm, mast, mast clamp, elevation scale, elevation bolts, coaxial cable, F-connector, receiver); a multi-satellite dish antenna manual, https://archive.org/details/manualsbase-id-434837 (reflector, LNB arm, mast, azimuth/mast clamp bolts, elevation pointers and scales, cable grounding block, ground wire, receiver); and a second dish maker's guides, counted as one source because they share their wording, https://archive.org/details/manualzilla-id-5988176 and https://archive.org/details/rca-hot-spots-satellite-dish-installation-guide (reflector, LNB support arm, mast, mast clamp, grounding block, grounding wire, elevation and azimuth). (4) For the cable carrying power up to the LNB: Tech Bulletin 9404, Home Satellite Dish System Installation Techniques, https://archive.org/details/coop-9404-home-satellite-dish-system. Licence: own work

The drawing: Drawn for this site on 2026-09-30 from plain geometry; no maker's dish, nothing traced. Licence: own work

How it works

The parts of a satellite dish in two views: the dish itself, with its reflector, LNB and mount, and the cable run at the house, with the grounding block and the receiver.

Read the full guide

The dish first, then the house

Numbers 1 to 4 catch the signal: the reflector, the feedhorn that faces it, the LNB behind the feedhorn and the arm that holds them. Numbers 5 to 7 are the mount: the elevation scale, the mast clamp and the mast. Number 8 is the coaxial cable. Numbers 9 to 11 are at the house: the grounding block on the outside wall, its ground wire, and the receiver indoors.

The dish is aimed two ways: elevation is up and down, azimuth is side to side.
On a home dish the feedhorn and the LNB are one unit, so many people call the whole thing the LNB.

Questions and answers

What is the LNB on a satellite dish?

LNB is short for low-noise block downconverter. It is the small box held in front of the dish. It collects the signal the dish reflects, amplifies it and converts it to lower frequencies, which a cable carries to the receiver indoors.

Why is the LNB not in the middle of the dish?

Most home dishes are offset dishes. The arm holds the LNB below the path of the incoming signal, at the bottom edge, so the LNB and its arm do not block part of the signal on its way to the reflector.

What is the arm on a satellite dish called?

It is the LNB arm, also called the feed arm or support arm. It sticks out from the bottom edge of the reflector and holds the LNB at the focal point.

What does a grounding block do?

It joins the cable from the dish to the cable going indoors and ties the cable to the building's ground through a ground wire. Installation guides say grounding helps protect the receiver system from lightning damage.