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I
have just finished installing a motorised satellite dish. I first heard
about these 10 years ago and imagined some massive dish sat in someone’s
back garden costing thousands of pounds picking up hundreds of channels
from around the world, a bit like the one in the picture. I’m not sure
how I got round to thinking about it again, I think it was due to me
looking at getting a dish for my Mum and Dads caravan so they could get
some of the free to air channels as the reception round there wasn’t
great. I had an old sky dish on the side of my house that I used just
for the free channels in my office until I got a new TV with an inbuilt
Digital decoder so the dish was just sort of sat there. I was wondering
what to do with it and had a look on ebay to see how much motors were
and were surprised just how cheap they were now and how easy they looked
to install. I don’t really watch a lot of TV but I did fancy trying to
fit one of these just to see if I could do it. As power to the motor is
supplied via the same cable as the satellite signal it didn’t sound like
it would be too much messing around.
I
think I paid about £30 for the motor and it wasn’t long before it
arrived. I was able to use the old pole and bracket that the old sky
dish had used to attach to the wall. I read the instructions and it
talked about making sure that the pole was vertical to the wall before
you attached the motor.. well it kinda was so I went about fixing it up.
The biggest problem I had at this
stage was getting the SKY disk to attach to the motor. The pole the sky
dish was originally attached to was tiny compared to the motor pole. I
went into the local satellite shop in Swindon and was met very a very
stressed man, who seemed to be far too busy to talk and basically told
me I was never going to get a bracket to attached that dish to that
motor and never going to pick up any other satellites on a SKY disk as
it was just too small and didn’t have enough gain and would need an 80cm
dish as a minimum, as he didn’t seem to be interested to sell me one I
left him to it. (I have since read a few forums on the internet and
there are people out there that have successfully done it with a SKY
dish). Not put off I went to Homebase to have a look as to what they
had so I could fashion my own bracket.
I
managed to find some ‘U’ shaped bolts that did just the trick and took
it home and fixed up the satellite. Now this is where my lack of
knowledge started to kick in. So I had this satellite dish on the side
of the house and now I had to find some satellites. Well my theory was
that I would just manually tune it into the old SKY satellite then go
back to the receiver and it would find the others as it would take that
first one as a reference. I manually tuned it in by pointing the dish
in roughly the same direction as it was before and all the other dishes
on the street were pointing and then used a Satellite finder that you
plug inline that has a needle that shows how strong the signal strength
is and makes a noise that changes in pitch depending on strength. This
is a similar thing to the tool that most receivers have it just has the
advantage of being able to use it close to the dish so as you move the
dish you don’t need to keep running back to the TV. It was only a cheap
one so doesn’t tell you what satellite it’s found just that there is
some sort of signal there.
Using this method I managed to find
the SKY satellite which is known as Astra or Eurobird1. I tightened
everything up and then went back into the house and tried to move the
dish around using the controls on the receiver. After trying for a
while I just could not find any other Satellite other than the Astra one
which was no better than what I had before I got the motor. I put this
down to one of two things. Either the dish wasn’t big enough like the
man in the shop had said or the new houses they had built along side of
my house was destroying the line of sight to the other satellites.
After a few weeks had passed it was
time to give it another go with another dish.. I found an 80cm dish on
ebay with a lnb for £25 and ordered that. The dish came and it was a
relatively simple job to swap the old SKY dish for this new one. I
aligned everything like I did before and after another hour of fruitless
searching I just couldn’t get anything more than just the one Satellite.
At this stage thoughts of getting
in a professional entered my mind but I didn’t want to give up just
yet. After all the idea of doing this was to try and do it myself and I
was in no rush to get the thing working other than to satisfy my
curiosity. After a bit of reading on the internet and finding a few
useful sites I had enough information to have another go.
The main sites that helped me were
www.youtube.com which has some videos of a guy doing an install and
digitalspy.co.uk which had a forum with a couple of people with similar
issues as to what I had.
After digesting this information I
came to this conclusion. It’s not as easy as it looked. My very
simplistic idea of sticking a dish on the side of your house.. moving it
a bit, find a satellite, lock that position in the receiver.. move it a
bit more find the next one etc. Well it does kinda work like that but
you have to get it exact. When you set the motor up the pole that you
mount it to has to be exactly vertical.. not nearly as mine was. The
motor arm itself isn’t vertical because as the dish turns it follows an
arc and unless you align everything just so you will not get all the
satellites. So as I had set mine up.. as I turned my dish it was
turning in an arc but my arc was only intercepting the true arc, the arc
with all the satellites at one point... as soon as I moved it left or
right I lost the true arc and was never going to get another dish.

This is how I imagined it. The
black line is the true arc and the dots the satellite and the blue line
is the arc my dish was following. Where the two intersected was the
place I had manually aligned the dish to.
Everything I was reading was
pointing out some key factors
-
Make sure the pole that you attach the motor too is absolutely
vertical.
-
Make sure that you align the motor with true south.
-
Make sure that you set the elevation on the motor correctly
Ok.. number 1 was easy enough. I
got out a spirit level. Loosened the wall bracket a bit and put some
thin plastic spaces under the bracket until I got it level and then
tightened it all back up.
Number 2.... hmm true south.
Apparently that’s not magnetic south but true south.. you have to
account for the variance . I didn’t have a compass and didn’t really
want to go and get one just for this. Some sites suggested using a pole
in a bucket and marking the shadow at noon. But then is that British
summer time noon? Or what and I didn’t really fancy trying to align the
dish to a shadow. So here is how I did it in the end, and I have to
bring in Number 3 at this point as well.
The first thing to do is to find
where about you are in the world. Latitude and longitude wise. I used
http://www.dishpointer.com/. Just put in your postcode and it will
give you this information. On the side of the motor was an elevation
setting which you need to work out what that should be based on your
latitude or on mine that was a handy latitude scale as well so I just
set that to what dishpointer.com told me. Now on dishpointer you can
zoom right into your house and move the pointer to exactly the position
on your house the dish goes. It gives you two lines. The white line is
true south and the blue is whatever Satellite is selected in the drop
down.
This gave me an idea of where south
was but I wanted to be a bit more exact so I decided to try and line up
the motor using the information that I knew.
I knew that I could find the sky
dish quite easily so I set the drop down on dishpointer.com to Astra
2A-B-D, below the map, where it gives the elevation information it also
has the Azimuth. Azimuth is positive clockwise position and measured
from True North, for where the Satellite should be located. 144 degrees
in my case. Well as the motor needed to be aligned to South I needed to
work out the South angle so 180 degrees minus (in my case) 144 degrees =
36 degrees. So my theory was if I would lock my motor on 36 degrees as
it had a scale on the motor to let me do this. I would then manually
turn the whole motor in the wall bracket until I picked up the Astra
Satellite. With the dish locked at 36 degrees as soon as I got a signal
the motor should then be pointing due south. I did this, tightened
everything up and everything worked great from that point on, I was able
to pick up other satellites and all the hundreds of free to air channels
that they carry

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