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> How to Install a Satellite Antenna
How to Install a Satellite Antenna
It doesn't take any knowledge to just install a
satellite antenna, what does take knowledge and skill is installing one
the right way. In
this guide I show you, step by step, how to find a good location,
mount, point and peak, and cable your new antenna.
Finding a good spot for your satellite antenna is
critical. Unlike OTA antennas, satellite
antennas do not necessarily need to be placed up high; it will receive
the same amount of signal sitting on the ground as it does on the peak
of your roof. The satellite is at least 36,000 km away, so a few meters
isn't likely to make a difference. Ideally, you'll want to place your
dish somewhere where it's easy to access for cleaning and maintenance,
but out of the way of everyday traffic; a good example would be on a
wall above head height or on the edge of a roof. There are three things
you need to consider when looking for a place to put your antenna.
Line of Sight
This is the
most important consideration. Satellite signals, like light, do not pass through solid objects.
The biggest problem in this area is trees. You'll want to pick a spot
where there are no obstructions, and you should leave enough clearance
so that nearby trees don't grow into the signal path. To determine
where your chosen satellite is located in the sky you'll need a device
called an inclinometer (pictured), which combines a compass and
protractor into one device. Lookup
the azimuth and elevation for your satellite, then use the compass
to find the azimuth and the protractor to find the elevation. The
satellite is located where those two coordinates intersect.
Alternatively, if you have a smart phone with built in camera and GPS,
there are a variety of augmented reality applications that show you in
real time where the satellites are located; just search for "dish
pointer" or "satellite finder" .
A satellite antenna requires a strong, sturdy mount. As
dish size increases, so will weight and wind loading, so take this into
consideration. Aditionally, a larger antenna will have a narrower
beamwidth, meaning that the signal will be stronger than a smaller
antenna when it's properly aligned, but will be more likely to drop the
signal if the dish moves.
The very best mount is on the edge of the roof of a
permanent structure. My two Ku band antennas are mounted to the edge of
the roof above my back porch. The exception to this is metal roofing,
which is too hard to properly waterproof and too hard to find a stud.
The next best place would be on a wood framed, brick, or concrete wall;
do not, however mount a dish to vinyl or aluminum siding, or any other
dimensionally unstable surface. The gable of a house is an acceptable
mount, provided the proper mounting hardware is used, but should only
be used when other methods aren't possible. As a last resort, you can
mount your dish to a pole in the ground, which I don't recommend, since
it's not as stable and too easy to inadvertently damage.
Grounding and Access
If the building has existing cabling that you want to
use, you'll want to get the antenna as close to where this cabling is
terminated as possible. This is usually located somewhere close to
where the building's electrical service enters the house, which brings
me to my next point. According to NFPA 70, the national electrical
code, all outdoor antennas must be grounded within ten feet of where
the cabling enters the structure. Usually this is accomplished with a
grounding block, which connected to either to an inter-system bonding
terminal, the building's grounding electrode, a meter or electrical
box, or a cold water pipe. If none of these are available, you'll have
to install a grounding spike, which should be at least 4 feet long.
You'll also want to ask yourself, how accessible is this
site? If you live in a climate where it snows, will you be able to
access the antenna to remove snow? Is it easy to reach the antenna from
the ground or from a ladder if it needs adjusted or repaired? And
beware of hazards such as overhead power lines.
I'll cover the most common mounts here, which should be
applicable to 99% of installations.
Direct to Wall/Roof Mount
Here's what you'll need:
- 2" lag screws
- 3" lag screws
- Lead anchors and ½" masonry bit (for masonry
- Silicone sealant (for wall mounts)
pad (for roof mount)
- ¼" drill bit
- Stud finder
Regardless of whether it's a wall or roof mount, it is
absolutely imperative to find a stud.
The roof and wall sheathing on most houses is thin plywood, or worse,
OSB and will not support the loads imposed on it by even a small, 45 cm
dish. In every case, the top bolts will pull loose, and in the worst
cases the entire mount goes. Using a stud finder makes it easy,
although tapping and listening for hollow spots isn't much harder. It
makes it easier if you know that roof studs are always spaced 24" apart
and wall studs are 16" apart.
Once you've found your stud, pre-drill the two center
holes in the foot of the J mast (#1 and #2). This prevents the wood
from splitting and makes it easier to line everything up, and it's an easy way to ensure
you're going into a stud: you should feel resistance and see sawdust
coming out all the way in. For roof mounts, apply the pitch pad now.
For wall mounts, fill the holes with silicone, then circle the all bolt
holes in the J mast with silicone. Drive a 3" lag screw into hole
number one, but don't tighten it all the way. Drive a 3" lag screw into
hole number two, and use a bubble level on the side of the mast to
adjust it until it's perfectly level, then tighten both center bolts.
You can now drive 2" lags into the four outer holes (nos. 3, 4, 5, and
For concrete, block or brick walls, you will only need
to mark the location of the four outer holes. Make absolutely certain
that they're perfectly level. Then, predrill with the ½" masonry
bit, insert the lead anchors, and drive in four 3" lag screws.
Here's what you'll
- Post hole diggers
- 3" lag screws
- 90° plastic pipe elbow
The type of post most commonly used for mounting a
satellite antenna is a galvanized steel electrical conduit, although a
galvanized fence post with the correct outside diameter will also work.
Start by digging a hole, which should be about 2 feet deep and about
12" across. It should be made larger in diameter towards the bottom.
Drive a few screws or bolts into the bottom of the post to keep it from
turning. With the level attached to the post, fill the hole with
concrete, making small adjustments as needed to keep everything
perfectly level. When you're done, double check all four sides with the
Give the concrete time to set up (hours, or a day or
two, depending on the type/brand and ambient temperature). Use a cable
tie to attach the pipe elbow to the post at the bottom, this will give
the cable protection from lawnmowers, weedwackers, etc...
Pointing and Peaking
This is actually the easiest part. Set the elevation at
the back of the dish. If the antenna has a skew bracket, like a Dish
Network antenna, go ahead and set it too, otherwise set the skew by
physically rotating the LNBF. Skew setting is irrelevant for single
orbital location circular polarized antennas. Do not adjust the skew after it's been
Put the dish on the pole, hand tighten the bolts and
connect the signal meter or receiver. Aim the dish in roughly the
direction of your satellite and slowly sweep it East and West looking
for a signal lock. You have now pointed the dish.
To fine tune the azimuth, sweep the dish very slowly
across the two degrees or so where the signal is locked, and make a
note of where the signal starts to drop, on each side, and point the
dish between these two marks. Now you will need to fine tune the
elevation. Loosen the elevation bolts and very gently raise and lower
the dish across the degree or so where the signal is locked. Make a
note of where it starts to drop, and again, position the dish between
these two points.
When the dish is properly peaked, tighten the elevation
bolts very, very tight. Do the same for the mounting collar, the two
sides of the mounting collar should be touching, or at least close
enough that a playing card wouldn't fit into the gap.
This is pretty much
always the weak point in any signal
distribution system, mostly because people don't seem to know how to
treat coaxial cable. Here's a hint, though, treat it like a very
delicate hose, not a wire; no kinks,
no sharp bends, no staples, and it should never be punctured. For more
information on cabling in general, see my
article on the subject.
Usually there will be two downleads from the antenna,
one for each polarity being fed to a switch, or for two receivers. Twin
conductor coax with a copper coated steel grounding line is widely
available and is easier to handle than separate lines. Make at least
two 4" loops of cable behind the dish, this provides some slack for
future upgrades or replacements. On smaller dishes you can wrap this
around the elevation bracket. The grounding wire should be connected,
via a grounding screw or lug, to the foot of the J-mast; on a post
mount you'll use a grounding strap. The grounding block should be
connected via a 10 gauge copper wire directly to the building's
grounding electrode, ground wire, intersystem bonding terminal, an
electrical box, or a cold water pipe.
Secure the cable every 18" with the appropriate cable
clips. I recommend the clamshell type (pictured) since they're easy to
use and seem to hold up well. Use silicone flooded 'direct burial'
cable for post mounted antennas. Near where the cabling enters the
building, make a few more 4" loops of cable; the bottom of these loops
should be lower than both the grounding block and the hole drilled for
the cable's entry. Most satellite grounding blocks have two barrels,
with the dielectric color coded blue to indicate that they're for use
at frequencies up to 2150 MHz, do not use the cheaper blocks with the
clear or white dielectric, as these are meant for CATV or over the air.
All of the wiring should be angled downward from the
grounding block, and upwards towards the hole where the cable enters
the building. This directs water away from the grounding block and
keeps it from corroding, and keeps the water out of your house where it
can cause structural damage. For good measure, use a plastic bushing
and silicone to fully weatherproof the cable entry hole. All of the
exterior fittings should be compression
connectors, and torqued
to 22-30 in-lbs. The connectors can be filled with silicone
grease beforehand to provide an additional
margin of waterproofing.