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Observing Tools Troubleshooting

• Turtle
  • Starting/Stopping/Running Turtle
    • I can't seem to get the Turtle GUI to start.
    • I moved by Scheduling Block from the job queue to the run queue on the Run tab, and it won't disappear from the run queue and run on the telescope. What do I do?
    • I closed down the turtle application, and there is some rogue observation running - what do I do?
    • I am not seeing state transistions (e.g. from "Activating" to "Ready or "Aborting") on the Turtle Monitor panel.
    • When I check the status of the processes running under TaskMaster on wind, I see that turtle.d shows Failure.
    • I opened up more than one Turtle application and now none of them are operational, but my Scheduling Block is still running. What do I do?
  • Configuration Problems
    • My source name is not updating. What's wrong?
    • I had the system configured, but now it is complaining and/or by GO FITS files are missing/incomplete.
  • Problems with Pointing/Focus
    • When doing a focus, my LFCs and Offsets are really huge - on the order of 20-80mm. What's wrong?*
    • I can't get fits for my pointing and focus scans and the antenna seems have weird values for H and V.
    • I'm using a dual-beam receiver, and not seeing any pointing source.
    • For a peak, I get the following message after the first two subscans: "No new corrections detected!" What is wrong?
    • I did a peak/focus, but the X-axis on my GFM plot does not cover the range I was expecting.
    • For a focus, GFM correctly displays the result, but after a few seconds, a dialog box pops up, telling that turtle has not received an updated focus, and asking me if I want to abort the procedure. What should I do?
  • Antenna Control and Slewing Problems
    • We went to access (perhaps to switch receivers) and now the antenna is slewing to a wierd location and/or complaining about illegal values.
    • Turtle seems to hang after a scan (e.g. Slew).
  • FITS Writing Problems
    • Turtle complains that it may not be able to write the GO FITS file.

Turtle

Starting/Stopping/Running Turtle

I can't seem to get the Turtle GUI to start.

Usually when this happens, you will be returned to the command prompt and no application will be launched. There are several reasons why this error may occur, including not having write permissions in the directory you are trying to run from. You should see a message instructing you what to do to get turtle to start. If there are no messages, ask the operator to ssh to wind as monctrl, and RestartTurtle. Restart the turtle GUI and your scheduling blocks should be runnable.

I moved by Scheduling Block from the job queue to the run queue on the Run tab, and it won't disappear from the run queue and run on the telescope. What do I do?

If this happens, there has likely been a disruption in communications between turtle and the control system. First, remove the Scheduling Block from the run queue by highlighting the Scheduling Block name, and then clicking the Remove button. Then, exit the turtle application. Ask the operator to ssh to wind as monctrl, and RestartTurtle. You will then be able to restart the turtle application and resume your observation.

I closed down the turtle application, and there is some rogue observation running - what do I do?

If you have exited the turtle application after promoting a Scheduling Block from the job queue to the run queue, and then asked the operator to restart turtle, the telescope will proceed to run the last observation you tried to submit. The solution is simple: remove all Scheduling Blocks from the run queue before you close the Turtle application.

I am not seeing state transistions (e.g. from "Activating" to "Ready or "Aborting") on the Turtle Monitor panel.

First, check on a status screen to make sure that there really are state transitions occurring in the control system. If there are, and the Turtle application is not picking them up, close the turtle GUI. Ask the operator to ssh to wind as monctrl, and RestartTurtle. Restart the turtle GUI and rerun your script. If the problem persists, restart Grail* on wind using TaskMaster and repeat this procedure.

When I check the status of the processes running under TaskMaster on wind, I see that turtle.d shows Failure.

Close the turtle GUI. Ask the operator to ssh to wind as monctrl, and RestartTurtle. Restart the turtle GUI and rerun your script.

I opened up more than one Turtle application and now none of them are operational, but my Scheduling Block is still running. What do I do?

First, ask the operator to abort your observation. Then, ask the operator to look up which processes your turtle applications are running under, and kill -HUP the process IDs. Ask the operator to ssh to wind as monctrl, and RestartTurtle, then you will be able to launch a new turtle application.

Configuration Problems

My source name is not updating. What's wrong?

I had the system configured, but now it is complaining and/or by GO FITS files are missing/incomplete.

Problems with Pointing/Focus

When doing a focus, my LFCs and Offsets are really huge - on the order of 20-80mm. What's wrong?*

Currently it is required that you slew to your source before you attempt to focus. If you try to focus without first being on source, the telescope will try to focus at the last location stored in the antenna, which is probably not on your source. You will end up with LFCs that are extremely unreasonable and you will have little or no apparent signal in your data. For the rest of the details, go here.

I can't get fits for my pointing and focus scans and the antenna seems have weird values for H and V.

I'm using a dual-beam receiver, and not seeing any pointing source.

For a peak, I get the following message after the first two subscans: "No new corrections detected!" What is wrong?

I did a peak/focus, but the X-axis on my GFM plot does not cover the range I was expecting.

For a focus, GFM correctly displays the result, but after a few seconds, a dialog box pops up, telling that turtle has not received an updated focus, and asking me if I want to abort the procedure. What should I do?

On occasion, there is a communication error between GFM and Turtle on focus scans, and so Turtle does not see the new value that has been calculated. It the calculated offset is small, simply ignore the failed update, and continue with your scheduling block. If the calculated offset is significant, you should probably abort the current scheduling block, and ask the Operator to update the Y LFC with the value reported by GFM. If this persists for a session, you should put a "Break" in your scheduling block immediately after the focus. When Turtle complains about the failure to update, ask to continue. Then, when the observation pauses, ask the Operator to update the LPC before answering the dialog box from the "Break".

Antenna Control and Slewing Problems

We went to access (perhaps to switch receivers) and now the antenna is slewing to a wierd location and/or complaining about illegal values.

The desired co-ordinate system (e.g. J2000) does not appear to get resent to the antenna if turtle/grail believes it is already known. If the Operator has moved the antenna to access using CLEO, they may have left the co-ordinate system as "Encoder". In this case, when the next observation is scheduled through turtle, the antenna may interpret a J2000 position as an (az,el) position, causing the antenna to attempt to slew to an unexpected position, or complain about an illegal value (e.g. if a -ve declination is interpreted as a -ve elevation). In this case, ask the operator to first slew to your target J2000 position, leaving the co-ordinate system as J2000. Then turtle should correctly recover.

Turtle seems to hang after a scan (e.g. Slew).

FITS Writing Problems

Turtle complains that it may not be able to write the GO FITS file.