Shoestring Astronomy Support

Hi,

I have an Ultima 8 with PEC and I am trying to figure out what exactly I need to autoguide with this telescope.

I have just bought the discounted DSI Pro, with the intention of using that as the guiding camera. I want to use a program such as MaxDSLR, Guide Dog, or PHD, to send adjustments to the telescope. The drive for the Ultima 8 has an RJ11 port for a hand controller. My laptop has a USB port, and I also have a USB to serial adpater from Keyspan.

I asked some one on a differnet mailing list who had a similar setup to mine. He used to use a Starlight Xpress with a relay box. He believed that I would be able to get a Shoestring adapter, BUT I would also need some sort of relay box to work with my telescope drive.

Any help as to the hardware I need would be greatly appreciated.

-Mike Durkin

If you have the handcontroller, it can be modified per schematic GP1 in this document:
http://store.shoestringastronomy.com/do ... idance.pdf
to add a ST4 compatible guide port to it. This would then mean that is should work for autoguiding with the GPUSB from Shoestring.

As for a pre-built relay box that you can purchase, I am ignorant on that topic. You might find advice on the some of the Yahoo groups or perhaps from Celestron themselves. Sorry.

Doug,

Thanks for the reply.

I was also looking at the website and came across this page:

http://www.shoestringastronomy.com/diy/diy.htm

Where I noticed you have an autoguiding system with a telescope that looks similar to mine. In fact, here is an image of the drive interfaces that looks almost identical to mine:



I am pretty sure that the hand controller can only make the RA drive run at double speed or zero speed, depending on which button you hit for RA corrections.

Do you think your autoguide system would be compatible with my mount? If so, do you have the plans, or do you sell the DB25 to RJ12 adapter?


Thanks in advance,

-Mike Durkin

Mike,

Could you provide a picture of your handcontroller also.

Thanks,

Doug,

I don't have a picture of the hand controller on me right now, however I did find an image on Astromart for an 11 inch Celestron Ultima, which seems to use the same hand controller:

http://www.astromart.com/images/classif ... 0805-3.jpg

That image shows the hand controller on the left, as well as a digital setting circles unit, which I don't have.

If you need a better image, I should be able to get one for you when I get home from work tonight.

Thanks again,

Mike Durkin

That picture shows me what I needed to know. That handcontroller looks just like the one I recently modified for a friend. When I traced out the schematic of what was inside the handcontroller, it led me to believe that the port on the mount is almost, but not exactly, an ST-4 compatible port. Thus, we added the relays per the GP1 schematic I noted in my first reply.

Thanks Doug. If I don't need or want to have the hand controller plugged in while guiding, do I have any other options? Or do I need to have something like the hand controller plugged in anyway to act as a relay box?

-Mike Durkin

Yes, you would need the handcontroller modified, and plugged into the port for autoguiding. A stand-alone relay box could probably be made, let me think about that one and get back to you.

Doug,

I took apart my hand controller and compared with the PDF file you referenced. I don't think my hand controller quite matches up with the document. I'm including images of the front and back of the curcuit board of my hand controller.

The single small switch in the upper right is for the LED light. The two small switches in the upper left are for the focus motor.




Do you still think that schematic GP1 would still be appropriate for my hand controller?

-Mike Durkin

Yes, if you put the relays shown in GP1 in parallel with the four directional switches, you should have an ST-4 compatible guide port on your handcontroller.

Hi,

After a couple of years, I'm again looking at my autoguiding options. I was wondering if the Shoestring adapter would work with an SBIG Relay Adapter Box (http://www.sbig.com/pdffiles/relay_box_instructions.pdf or http://www.optcorp.com/product.aspx?pid=2571) when connection to the hand controller port I have specified in my earlier posts. I am assuming that I would have the shoestring output connected to the relay box input, and then the relay box output to the hand control port on the mount.

-Mike Durkin

Mike,

Yes, I believe that will work.

Thanks Doug,

I've just ordered a USB Shoestring adapter and the SBIG relay box. Hopefully this combo will work for me.

-Mike Durkin

I am pretty sure that the hand controller can only make the RA drive run at double speed or zero speed, depending on which button you hit for RA corrections. ????

That's correct Faqeer.

In the end I just needed the USB Shoestring adapter and I made my own cable to go from the Shoestring Adapter to the hand controller port on the drive. I have been using this set up for a few years now and I have usually been pretty happy with the results.