SVP GoTo going wrong direction. Help?
Posted 22 January 2011 - 01:59 AM
I'm encountering a problem that I had the first time I ever set it up, and I can't remember what the fix was.
In short, the scope goes the wrong direction. It goes right when it ought to go left.
I go through the setup and put in my coordinates North and West correctly, set my local time, and time zone. In California I set -8 hours time zone. I tell it to park the scope and I do a rough alignment on Polaris. Then I go to do the 3-star alignment, choose Capella, and the thing slews to the right. If I choose an object to go to, the scope goes away from that object.
Anyone know the pitfalls of the SVP GoTo? I'm fairly positive it isn't set for Southern hemisphere or anything. The location setting with North Latitude and + West Longitude should tell it where I am.
Posted 22 January 2011 - 03:22 AM
Posted 22 January 2011 - 08:53 AM
I don't know about your particular mount, but a similar thing can happen with a Nexstar mount. There is an option in my mount called "Cordwrap" which can be turned on or off. If it is turned on, it attempts to move in whatever direction is necessary to keep a power cord from an external supply from wrapping around the mount.
Basically, when cordwrap is on, the mount establishes a no-cross line which the scope will not cross during a goto. Lets say the no-cross line is at 90° azimuth. If your scope is pointing at 80° and you try to goto an object that is at 100°, instead of moving the short 20° to get to the object, it will take the 340° path which seems to be the wrong way around.
So, if you have such an option in your mount, you may want to turn it off.
Posted 22 January 2011 - 09:36 PM
There is a firmware bug in the SVP GoTo for setting location time zone. When you get to setting time zone, it displays +8:00. You can use the controller's up and down arrows at the bottom to change the + to a -, as I need -8:00 for California. If you use the down arrow at the bottom on the left, the setting does not stick, and your setup will stay at +8:00, which you can confirm by going back to setup location for time zone, where it will display + again. But if you use the up arrow at the bottom on the right to change the + to a -, then the setting will stick.
So the problem I was having with the scope slewing right when I was expecting left was probably due to the incorrect +8:00 time zone, instead of the correct -8:00 time zone.
After a couple hours outdoors last night with no success figuring out the problem, I brought the rig inside to try and solve it. I finally set it to align to Arcturus, which I expected to be near the horizon, and the scope slewed up towards the zenith, then WHITE SMOKE CAME OUT OF THE GOTO CONTROL UNIT. (Not the hand unit, but the control unit which the hand controller plugs into.) I didn't dissect the unit to see what fried, but it was white smoke typical of smoking a resistor. I took the whole shebang to the Cupertino Orion store today to be sent for repair or replacement, and we hooked up another control unit (as mine was dead). I showed them how I was setting up the unit and they showed me the bug with the down and up arrow keys.
So I'm pretty sure the entire problem was the time zone setting, but now my GoTo unit smoked, so I'll have to wait for it to come back from repair.
My firmware was 3.23, and they're now up to 3.27. They're going to flash my unit with the updated software while they have it.
Posted 22 January 2011 - 10:34 PM
Posted 23 January 2011 - 12:24 AM
Posted 23 January 2011 - 07:44 PM
One simply sets the Latitude and Longitude. The hemisphere is inherently evident by those settings, there is not a specific setting for hemisphere.
Make sure it's set for Northern hemisphere
Posted 23 January 2011 - 08:25 PM
I was operating the rig for several hours outside, trying to figure out the problem with the scope slewing the wrong direction, so it wasn't an immediate fault. Ultimately I brought it indoors to try to figure it out, and it didn't smoke until I tried to align it to Arcturus. The only physical problem I noticed is that the DIN jack for the declination cable was physically loose and the center plastic part nearly falls out. They're going to handle that with the repair/replacement of the control unit. I have no idea what caused the unit to smoke, it was quite surprising.
Yikes, Bugsi, I cringed when I read the part about the smoke! I just hope the repair doesn't set you back too much. Could it have gotten damaged during your move? Maybe something corroded during the year in storage? Good luck with it, and please let us know how it turns out.
Posted 11 February 2011 - 07:41 PM
Orion decided my control module was toast (duh), and replaced it for $100. They also updated the firmware on the hand controller to version 3.27 (which is for both the SkyView Pro and the Atlas GoTo product) and the updated version does not have the bug with the down arrow on the hand controller not making the time zone setting stick. (The bug is fixed.)
One other thing, my GoTo controller does not fit properly on my SVP mount's leg. It's supposed to snap on, but mine does not fit. It turns out the SVP was updated in 2006 to a model with thicker tubes for the legs. They said a metal clip on the bracket is also an electrical ground, but I can't imagine that this was in any way related to my control unit going up in smoke. They recommended I use wire ties or something to securely hold my GoTo controller to my tripod's leg. I'll work something out.