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Encouraged
by my wife, who found lifting and carrying the tripod and telescope outside for
each viewing session too much on her own, I have installed a dome for
my Meade LX90.
I bought a fibreglass dome from Sky Domes of Bude, Cornwall: see www.skydomes.co.uk. Sky Domes is a friendly outfit in a lovely part of the UK. I hired a van and collected the dome myself.
The access to our backyard where the dome is positioned is not easy so I purchased a 2m diameter dome that comes in several pieces. The dome wall was in three parts and the dome in four. The parts were easily lifted and manoeuvred by two people, but the assembled dome needed three to place on top of the walls.
The following pictures show the assembly with comments which might be of use to others....
Planning
the best view
I needed to position the dome out of way of the most used areas of our yard yet giving as wide a view of the sky as possible. The final compromise allows us to view most of sky apart from northern sky below Polaris.
I also decided to raise the dome by making a base of five courses of bricks. This gave slightly better seeing over the house!
The first building task was to assemble the dome wall sections (finger tight) and chalk out the inner and outer wall circumference for placing the brick courses for the base.
The dome wall sections were placed into position and its outline chalked on to the patio.
Adequate clearance was allowed for sweeping leaves and rubbish from the rear of dome,
as well as clearance for the front lower shutter.
The
dome wall was removed and hard work commenced!
The five courses of bricks were laid, together with an entrance step. Then the centre of the ring of bricks was excavated down to solid earth before two tons of concrete were mixed and poured.
The concrete had to be poured over several days as I was afraid the pressure of the so much fresh concrete poured in one lot would burst the wall!
Note also the black conduits pre-positioned through the brickwork for later installation of
power and network/telephone cables from the house. The white 24mm waste pipes
were also pre-positioned within the concrete to allow cables to be easily pulled from one side
of the dome to other. I took care to cover the tops of these pipes to keep out
the concrete. From the wall to near to the centre,
I also
installed another pipe for carrying cables, both 12v power for the
telescope and serial for connecting my laptop computer to the Autostar.
With the cables underneath the floor, this would make it
safer in the dark! I placed the centre pipe far enough away from dead centre of
the dome to allow for the
installation of a mounting pier for the telescope.
Final pouring of concrete complete
Now to wait for several weeks
for it to cure before assembling the dome. I went on holiday!
Assembling the walls of the dome:
The dome came supplied with all the bolts, screws and silicon to assemble and waterproof the joints. A real 'big boys' Meccano job!
The three wall sections were assembled on the base and the pre-drilled holes in the fibreglass marked on to the brick base. The dome wall was then lifted off and the holes drilled into the bricks of the base where marked.
A ring of silicon to fit the bottom of the dome was put onto the concrete base and the
dome moved quickly into place on top of it and bolted down. (Remember to have worked out where you
want the door before getting this far!)
Assembling the dome roof sections
These sections must be assembled on a flat surface and lifted onto the wall as one assembled unit.
The assembled sections were sealed with silicon, and screwed and bolted tight before adding the sliding hatch.
Moving
the sliding hatch on the assembled dome
I found I had to use a silicon spray on the runners of the sliding hatch to ease movement.
Following completion of the dome, I ran two conduits from the house to carry power and network cables. Conduits were separate to ensure electrical safety between power and signal supplies.
I have installed terminal blocks in the dome for the mains electrical supply.
I pulled two lengths of computer CAT5 network cable through the second conduit. One cable was terminated with a CAT5 socket for a network connection to my home LAN (100Mb), which also gives the computers access to internet though my broadband connection.
The second CAT5 cable is terminated into two 4wire RJ11 sockets, one of which is used for a telephone connection.
Coffee time for the builders and a look at their completed task
This picture shows both the view from inside the dome looking out through the telescope viewing hatch, and the view looking out of the door.
The hatch has two levers to provide secure locking. The front door has a secure mortise lock.
Note also one of the wheels supporting the dome as it runs along the top of the wall.
Later, I installed a steel pier to mount the telescope - having a tripod in a dome is not advisable.
The pier needs bolting to the concrete base with 3/8" rawl-bolts. It took me some effort to drill the holes; my concrete for the base had been made with aggregate and drilling through this took some considerable effort.
Photographs by Pat Cuckney 
The dome makes viewing sessions much easier and more productive - I can really recommend one.
January .... no damp, cold feet from viewing standing in the snow!
Setup within Dome ready for operation. There is room for workstation with laptop PC (running either SkyMap Pro or Starry Night and connected to the Autostar) and small monitor for displaying images from Meade Electronic eyepiece when I have visitors.
Note the homemade Astrocam mounted on Meade Flip-Mirror system with Meade zoom eyepiece.
Laptop PC and eyepieces are not kept in the dome for security reasons.
I have used a film/slide projector stand for the laptop and monitor; this provides a comfortable working height for the laptop keyboard.
To the right, a more recent view of a homemade console that I now have in my
Dome;
the telescope has also changed to Meade LX200GPS 10".
The console is about 4' high - the telescope forks just pass over the top as they rotate!
Connections to the LX200GPS are now through an old laptop at the top which runs RJ45/COM link and a Meade Autostar Network server which I can use from a computer indoors or from the computer at the bottom of the console. The bottom computer is the main host for operational control - it has a screen tipped up onto its back and a small keyboard on a shelf. I sit on a plastic single step utility step. The bottom computer runs Remote Autostar through the laptop, image capture programs (AstroArt, Starlight Xpress, DSLRfocus or Webcam capture), and SkyMap Pro for GOTO driving of the telescope. The bottom PC runs ASCOM POTS to share COM port to telescope between AstroArt and SkyMap Pro.
I had tested
my new Meade LX200GPS telescope outside the dome before mounting on the pier in
the dome and all
systems seemed to operate OK. However, when moved to inside the dome
the GPS could not get a fix from the satellites; my dome is made from fibreglass.
I saw on the web that others had experienced similar problems - I wanted the
GPS to make for easy setup to provide my wife with 'immediate' viewing when I
was out so I installed a re-radiating antenna which has a GPS receiving aerial
outside the dome and then re-transmits a signal within the dome. This worked
first time. The system was from GPS
Central.ca and called Tri-M Mighty Mouse Wide Re-Radiating Antenna. The
supplied cables are longer than they appear in the image on right - each cable exceeds 16ft.
I have the external antenna for the Mighty Mouse mounted on top of a vertical post made of plastic downpipe: see left (the antenna is mounted flat across the top of the pipe with cable routed inside the pipe). The internal re-radiator antenna is mounted at the top of the fixed inside wall of the dome - about 1 - 1.5 metre from the GPS receiver in the Meade arm. The supplied cables are more than adequate for my cable runs which are not the shortest route. I feed it with 12VDC from and old PC power supply which also supplies the telescope - it thus is powered up when I power up the telescope.
With the GPS operational I can now Park the telescope between sessions and after a hands-free power-on routine it is immediately available for use.
I am worried about the damp and humidity within the dome effecting the telescope and its components, so I have built a small heater. I took a large metal biscuit tin and cut two dozen ventilation holes in it. Inside the larger tin I installed a smaller tin with a 100watt light bulb inside. I took a 12v fan from a computer with a small transformer/rectifier and installed these inside the large tin as well. The whole unit now provides a small amount of warmth and circulation within the dome, 24hours a day. It seems to drop the humidity by a few percent which I hope is helping? Click heater image to the right for more information,
(I have since found an old desktop computer that I use as main operating computer in the Dome and leave running all the time to provide some air movement and some 80W of heat.)
I live in a suburban area which is well served with street lights. One light,
in particular, shone through a gap between my neighbour's and my own
house. I wrote to the Technical Director of my own local authority, Solihull MBC,
asking if they could provide a shield. Within weeks they had solved the 
problem!
Apparently, they could not obtain a shield for the old lamp we have; but the Street Lighting Engineering department, in true problem-solving engineering spirit, have added 'gaffer' tape to the glass enclosure and the problem was solved.
My sincere thanks to them for a very good, prompt service.
So, if you have light pollution problems, write a nice letter to your local authority and see if they can help.
See 
http://britastro.org/baa/component/option,com_wrapper/Itemid,56/
for UK Dark Skies organisation.
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