Planetarium Star Projectors

[djeric68]

I thoroughly enjoy reading your posts about these projectors.

Saw this on cnet earlier today...

http://news.cnet.com/8301-17938_105-...jector-museum/

[SpitzSTP]

I thoroughly enjoy reading your posts about these projectors.

Saw this on cnet earlier today...

http://news.cnet.com/8301-17938_105-...jector-museum/

Hi Eric, thanks for the link. I know this man, he is a great guy and I admire his collection. I've been out there a few times to see it. There are only a few people in the USA that I know, that collect these machines. A good friend of mine in Cave Creek, AZ and another close friend in Georgia. I am so glad that my posts are of value, thank you for mentioning it I have been slaving over the Saint STP lately trying to get it fully functional. The new Xenon PSU's finally came from Germany and they are mounted on a sled in the control rack. The latest effort has been to mount the xenon ignitors in the star chambers. I have also had a number of personal issues.. got laid off in December, been searching for a job. It's always something, isn't it ?

[SpitzSTP]

Old and new Xenon ignitors. I am using 5 slip rings each for the + and - trigger signal plus 2 slip rings for the cooling fan power, hence a 10-position terminal strip. The new solid-state ignitors from Germany are much smaller and lighter than the originals which used a heavy transformer. I attached the new ignitors to an aluminum plate having the same footprint as the old boards so it will mount using the same screw holes. These go into the north and south star chamber hemisphere, respectively. The set of 8 inline disconnects made of silicone rubber, from Connectronics Corp, cost a whopping 400.00 just for those.

[SpitzSTP]

Two Xenon PSU's from Germany, mounted in the control rack for the Saint. The short-arc lamps in the star chamber are 300 watts each (total, 600 watts). The bulbs run at 14 volts 21 amps, with a trigger voltage of around 24KV.

[Jem]

Great info. I love reading your posts and the constant quest for getting these things working again.

Keep 'em coming

[dar303]

Hi fellow planetarium freaks!

It looks like I'll be the proud owner of a Spitz A3p in the near future and I would need some advice!
I will get it for free from a museum that is upgrading to digital and at the moment it is just put on a pallet as it is and I guess I need to dissassemble it to treansport.
The control console is gone many years ago and it is run from a mac (g3?) with a custom interface by DATATON in Sweden. Is it possible to build an analog controller for it, are schematics and system descriptions available?

Also, how big is it, the actual moving mechanics is about 2 meters but how wide?
The base is about 1x1x1meter with 2 meter arms to hold the moving part, correct?
The console is gone but is there a separate power supply or is it in the base of the unit?
Is it easy to take the unit apart intom more mangeable pieces?
They said there was a intermittent problem with the lamp driver but that should be fixable I guess.

I have a friend who runs an event firm that specializes in rave and techno parties and he gives me free storage space and places to run the machine for an audience that will really appreciate it I think!

Regards

/Daniel, Sweden

[m2b]

Hi fellow planetarium freaks!

It looks like I'll be the proud owner of a Spitz A3p in the near future and I would need some advice!

The A3P is a great machine and built like a tank. It should give you many years of excellent service. I rebuilt one for myself so have an intimate knowledge of the machine.

I will get it for free from a museum that is upgrading to digital and at the moment it is just put on a pallet as it is and I guess I need to dissassemble it to treansport.

Great price! I wish I was that lucky! Yes some parts of the projector are somewhat fragile and can be easily damaged. It is important to take it apart and then support sections properly. The machine is made up of three main sections the star ball at the top this is connected to the central core which is supported by four legs to the mounting plate which sits on the wooden pedestal and finally the planet sun moon projector sections. The most important thing to remember is never try and lift the planet projector section from the outside where the actual projectors are. You should only support it from the large round section that holds the actual planet mechanisms which is attached to the center drive on a 23 1/2 degree plate with four bolts. Always hold and lift from this end. Lifting from the outside end WILL cause serious damage. The star ball can also be removed but you must first remove the light source from the star ball which is accessed from a round port on the side of the star ball.

The control console is gone many years ago and it is run from a mac (g3?) with a custom interface by DATATON in Sweden. Is it possible to build an analog controller for it, are schematics and system descriptions available?

The original control console contained the various power supplies for the machine which consisted of a 6.3 volt supply for the various individual projectors like the planets etc., a power supply for the arc lamp, a DC supply for the DC drive motors as well as DC for breaking of the AC motors and a variable AC frequency supply for the AC motors and an amplifier to amplify the AC control frequency generator to a level to run the various AC motors. Much of this 1950's technology broke down and many replaced it with more modern electronics like your Dataton system. The projector drives are actually quite simple to replace if you want to sr up the machine for manual operation as I did. I think you will find that many of the power supplies will probably be found in the wooden base of the unit your getting. If not, it is easy to convert over as I just used a simple Variac to a full wave rectifier and then to the drive motor.

Also, how big is it, the actual moving mechanics is about 2 meters but how wide?

About two feet or 2/3 meter.

The base is about 1x1x1meter with 2 meter arms to hold the moving part, correct?

Yes

The console is gone but is there a separate power supply or is it in the base of the unit?

I would guess that is where they put it. There should be several as outlined above.

Is it easy to take the unit apart intom more mangeable pieces?

Yes, very easy as outlined above.

They said there was a intermittent problem with the lamp driver but that should be fixable I guess.

There is a transistor then tends to go out on the starter which is usually the problem.

I have a friend who runs an event firm that specializes in rave and techno parties and he gives me free storage space and places to run the machine for an audience that will really appreciate it I think!

People LOVE the old style planetarium machine and the sky they project. Just remember that you must have a pitch black room for them to work their best. If I can answer any other question or if something needs clarification, just ask planetariums are a lot of fun!

Ron

Regards

/Daniel, Sweden

I must make this answer 15 more characters longer....that's what it said??????? Please see answers in your original post above.

[dar303]

Thanks for all the information, seems doable now!
I might go and get it in two weeks or so. Do you by any chance have some mechanical drawings, service manuals or good photos? I need to rent a van and it is quite a long drive, will probably only get one shot at bringing the projector home!

I guess all the screews, bolts and nuts are inch based sizes, UNC/UNF, right? Need to bring the right tools, we are all metric around here!

[SpitzSTP]

Hello, here is a Spitz A3P. The hardware should NOT be metric, it will be Standard or SAE. I have access to documentation, please let me know what you need and I will be glad to help you. These are fabulous machines

Thanks for all the information, seems doable now!
I might go and get it in two weeks or so. Do you by any chance have some mechanical drawings, service manuals or good photos? I need to rent a van and it is quite a long drive, will probably only get one shot at bringing the projector home!

I guess all the screews, bolts and nuts are inch based sizes, UNC/UNF, right? Need to bring the right tools, we are all metric around here!

[m2b]

Thanks for all the information, seems doable now!
I might go and get it in two weeks or so. Do you by any chance have some mechanical drawings, service manuals or good photos? I need to rent a van and it is quite a long drive, will probably only get one shot at bringing the projector home!

I guess all the screews, bolts and nuts are inch based sizes, UNC/UNF, right? Need to bring the right tools, we are all metric around here!

Yes the projector screws etc. are English rather then metric (which is interesting considering that the English use metric [ I do believe that we are the last of the backward countries]). While I can give you sizes of nuts that are on my machine you might encounter something different as I have yet to meet two of these machines that are exactly alike.

You will first remove the coordinates projector which is at the far south end of the planet cage. This is done simply by pulling a two pin plug and the turning a finger nut by hand. There is also a screw (normal screwdriver) 180 degrees around the same top side of the projector. The unit then just slides off a mounting pin. The Earth continent projector ( a plastic sphere mounted on the central core) is removed by simply opening another finger screw and unplugging a two pin plug. You may find a lot of other projectors mounted on pins on the bottom plate of the projector (this is the six sided aluminum plate about a meter across that sits in the wooden base) which will require a screwdriver.

The star globe will come next after you open the arc lamp access plate just to the left of the Orion star group (easy to see as all of the main stars are lenses) and remove the round plate via the four thumb screws. You can then reach inside and unhook the starter and arc lamp assembly from its yoke. This is held in place by gravity and is easily lifted off. Then replace the access plate (so it is not lost) and then remove the star ball itself by removing the four thumb screws at the base of the star ball where it attaches to the projector. The star ball is easily dented so be careful with it.

Next comes the planet cage which is removed by releasing a multiple pin plug and the removing the four 7/16 inch hex nuts which are on the main color which holds the planet cage at 23.5 degrees off the diurnal shaft. This is a two person operation as one person must hold the planet cage by the large round central area just below where the nuts are removed. NEVER try and hold the planet cage by the projector plate at the far south end of the projector or serious damage WILL occur.

You will need to access the wooded base to disconnect the main control cables (there are four) but who knows as the original control console has been replaced. The central core of the projector as well as the hexagonal plate should be removed from the wooded base and in most projectors they are attached to each other by four metal spacers about four inches long. They should remain connected to the metal plate as thew provide clearance for two drive motors mounted on the bottom of that plate.

You can now transport the projector in this many pieces. Star globe, planet cage, central core, wood base, many small projectors, a bunch of cables, and several different power supplies and the new control units.

There is not a lot of printed material on these projectors, but they are fairly easy to set up and adjust.

Unless the operators of this site have a problem with mentioning other sites (and I apologize if I have done wrong) there is a complete photo essay of my rebuilding of my A3P with many pictures on www.observatorycentral.com under the section "Planetariums as a hobby". To see any pictures you must register but it is simple and free. There is a lot of information on the A3P for your perusal and you can go directly to my rebuilding of the A3P by going here: http://www.observatorycentral.com/in...ndpost&p=18739

This should give you a fairly good idea of how the projector is put together. Again, any questions, please ask. Having a planetarium is really great fun.

Ron