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So, I am planning on situating my scope outside permanently and automating so I can work inside (just too cold in the winter in SLC to work outside).
Here is my plan of attack, maybe I could get some guidance from the group to see if I am headed down the right path.
I have built a 12" reinfoced concrete pier for my scope. I purchased a Dan's pier top plate and the Motel O'scope he offers here (www.pierplates.com). I thought this would be a great deal (instead of spending mucho dollars on a POD). He lives in SLC so I actually went to his house to see his set up and it looked very solid to me.
I have a CGE (non-pro) mount, 11" Edge HD OTA, Microtouch wired focuser, Starlight Xpress H9C with hyperstar, & GPS.
I plan to run conduit from the scope pier to the house.
So far, my plan is to run a CAT 5 cable from the mounts electronic pier to the house and convert in the house with a CAT 5 to USB adapter.
I would like to upgrade my microtouch focuser to the wireless version and run the USB connection to another USB to CAT 5 conversion and then run a separate CAT 5 cable through the conduit to the house with another CAT 5 to USB converter.
Lastly I plan to do the same for the camera (USB to CAT 5 converter to CAT 5 cable through conduit and CAT 5 to USB converter in the house).
Essentially I will have 3 each CAT 5 cables running through the conduit (will have extra just in case).
As far as power, I will run power from focuser, camera, and scope to a power strip inside the motel o'scope and then run to the house. All converted is switched from DC to AC with upgraded cables.
Am I missing anything here? Sorry for the longer post, but it's always nice to get a few extra eyes on the plan.
Lisa I would use Shielded Cat5 and also Underground Cat5. You don't want cross talk on the wires, but that is just my 2 cents worth.
Your situation is different from mine in that I have a building around the pier. But if I were in your situation I think I would still do the same thing as now: Have a computer at the pier (it could be just a little netbook), with direct USB connections to all the astro gear, then use a single CAT5 cable to carry ethernet from that computer to another inside the house. Then, using any one of several remote desktop programs, you can operate everything as if you were there at the scope. I use the same configuration in the field, except that the ethernet connection is sometimes replaced with a wi-fi connection, which is almost exactly the same structure.
I've never tried a USB to CAT5 converter, but I know that many USB devices don't even like going through a hub, so I would not be surprised to find major problems with this connection method. One thing to remember with USB is that it isn't just a matter of signal integrity that limits the length of cables - there are also timing issues. That is, there are transactions that must be completed in less time than it takes the signal to travel 50 feet. The converter will take care of that at the low level, but secondary effects can propagate up the stack.
I'm planning to lay conduit to my obs. early fall (waiting for the flower bed I'm going through to bloom out). To take Bob's point one step further, I've talked w/my neighbor (mast.electrician) and he says they always lay 2 separate pipes for power and communication cable. The hole is already open and conduit is cheap, that way there's no possibility of cross talk. Also run a nylon pull string w/the cables in the conduit in case you want to pull some different cable through at a later time. Lisa, I'm planning to go the route Greg explained, but do you have any links to those cat5 to usb converters? I'm interested how all that would work (and cost). Thanks
This is what I was looking at (very cheap)
My husband is an electrical engineer and would agree with the two conduits and pulling with nylon wire. I figure I'll try out this method and if it doesn't work, I can still go back to what Greg is suggesting...I'm just a little bit worried with temps in Utah affecting my new alienware laptop.
Two things stand out to me in the product description:
1. The price - it's too low for a device that would do this job properly and reliably (IMHO).
2. "Note: the distance and adapters may affect the performance of some devices down to USB 1.1 speed". This suggests that it's not even handling the timing issues, it just drops down to USB 1.1 speed (12MHz) if the cable is too long.
Marc, That is what I did for running power and internet out to my Observatory. I have one pipe for power and one for data. Since I have to be 18" down because that is code, I went with the underground Cat5 that has the grease in it to protect it from water.
It does make sense to run power and data in separate conduit and might even be required by code, but I think this is more for safety reasons than data integrity - you wouldn't want a power line shorted to a data line, which could happen with enough water and corrosion. Since ethernet uses differential signals through twisted pairs it should have very high immunity to crosstalk (in either direction) with the power lines. The purpose of shielded data cables is not so much to prevent crosstalk as to prevent radiation of common-mode noise, which is often a problem with computers. RF noise generated by the computer gets into the data cables with the same level & polarity on both positive and negative sides of the data pair. It doesn't affect the data communications, but can interfere with radio & TV signals if it radiates from the cable. Shielding the cable (as well as the equipment at both ends of the cable) reduces that radiation.
Lisa, I think you're smart running your idea through a group like this before you really get started on this project. I wish Charles would have thought of this a year or so sooner.
I have my C-11 set as a permanent fixture in my back yard and if I had to do it all over again... I'd move LOL.
Actually, for my location it seems to work. My winters are cold as well. -20F in the dead of night is not unheard of. I do use my laptop outside and I've read about the concerns of those low temps. Never having an issue "so far" I think the concerns are valid but with careful planning the unspeakable event can be avoided. I usually drape a light towel over the laptop once I get my imaging session up and running (all from outside of course) and then only check things every so ofter. Maybe I'm gambling with fate. Maybe not.
Being able to run the show from inside would be the ultimate so that' what I'd do different if I change things now.
I do have reservations about the Motel O'scope because I try to have 3 - 6 star parties a year at my house using that scope and and my C-8. From the photos it looks like the base system might block a visual observer from getting up close to the mount in certain situations. I'm currently sing one of those all weather covers from Telegizmos. I've had the same cover for two years now through rain, snow (49" in one storm) hail and every other thing mother nature throws at us. One thing you should so - no matter what cover you use - unplug your hand controller and bring it inside. The heat inside these things builds throughout the day and can damage it.
Lisa, whatever you decide to go with it's a great idea. I finished my roll away observatory a month or so ago http://marcbasti.com/category/observatory/ and it's so nice to be able to go out and be ready to image in 5-10mns. And probably even better, closing every thing up in 5-10mns at 3am. Marc PS Dans PPates A++
Marc, looks like you have some trees to contend with in your yard! I do too, but I hope they don't interfere too much. I have trees and mountains! I thougth about a roll off observatory...but the Motel O'scope is so much easier...and I'm lazy. :)