The 60" autoguider program runs from the PC. Boot the PC and make sure the camera, both tv screens and video pointer are turned on. Adjust gain of camera until you can see stars, but the stars don't "bloom". The guider will work with stars that are very faint, so don't worry about that.
The guide rate on the TCS PC should be set to .50, this will happen automatically whenever the Realtime System is started. It can also be reset thru the TCS60 program.
To start guiding, slew to the star you want to observe. If the program is not running on the PC, either reboot the pc, or type in "cd \" then "start". This will start a batch file on the pc that lets you select the version of the guider you desire. There are currently three versions, with different programs for the FAST, ECHELLE, and AFOE. Each of these programs varys a bit, this documentation will follow the FAST guider.
After starting the program, the main menu will come up. There is a status box near the top which shows values for the position you are guiding from, the Guide State, and the dome position. Below this to the left is the main menu, which should look a bit like this:
G - Start Guiding
S - Set Various Parameters
R - Rotate Spectrograph (FAST GUIDER ONLY!)
C - Toggle Communications Now (Off)
H - Home Dome
T - Dome Track (Off)
E - Exit Program
Choose "G" from the menu to start guiding. Unlike the 48", the 60" has no "topbox". The pickoff mirror is fixed, and if you do not see a guide star, you must reposition the telescope.
A high contrast image of the star to be used for guiding is best. We have found that the guider works reasonably well as a "spilled light" guider. That is, the guider can also work using the light from a galaxy or star that falls on either side of the slit.
Once a star is in the field, use the pc arrow keys to position the cross hairs on top monitor on a guide star, then type a G to guide.. You can use the keypad keys 7,9,1&3 to move diagonally as well, as long as NUMLOCK is off. When the cross hairs are positioned, type "G" to start guiding.
While guiding, messages will be shown with the x and y axis centroid error in pixels. You will see another message starting "Moving" each time it moves the telescope. Errors should be >= 3.0, and motions should be less than 3, but average 1. If it makes too many motions, or "wobbles", ie. continues to move west, east, west east, etc, adjustments should be made to the variables. Possible changes to consider are the size of the error for which a correction is made, and the length (in time) of the applied correction. Values too small will mean the corrections won't keep up with the errors. Values too large may result in oscillatory motions. The default values are believed to work for most positions in the sky, but you may find some places that require different values.
If the guider loses the star, the message "object gone" will be shown. Realign the crosshairs in bottom monitor if needed, for later reference..
If you wish to suspend guiding, or leave the program, hit any key on the PC. This will bring you back to the top level menu.
This brings up the parameters menu, shown below:
S : toggle audible warning now on
This controls a noisy warning if object is lost.
J : Jog Dome
Use this to move dome back and forth during cold weather
T : set threshold prior to move now = 2.400000
controls how far you let position drift before correction
G : change length of time that correction is made (range
is from 1-1000)
A : aquire new position for guiding
set up on new object
Q : return to main menu
This brings up the rotation menu, shown below.
The rotator power must be on to rotate. The switch is mounted on the east side of the telescope mirror cell. This switch should be turned on before rotation, and off after rotation.
All rotations should be done with the telescope at or near zenith. ("Stowing" the telescope will turn the tracking off, be sure to turn it back on.)
Note that position angle on sky is limited to angles between 110 and -110, because of the way the FAST instrument is cabled. If you are moving thru an angle span of more that 70 degrees, you need to go out to the telescope and insure that the cables don't get caught on the CCD electronic box. Always check cables after rotating!!
For object position angles greater than 90 and less than 270, subtract 180 from your number. For angles between 270 and 360, subtract 360 from your number. It is best that the astronomer do this rather than the computer, so that you know exactly what value you enter. This helps because (1) you will not be confused as to which side of your slit corresponds to which direction on the sky, and (2) you can be aware of a possible cable problem as described above.
There is a program available on flwo60 called parallactic , which takes as input the hour angle and declination of your object and gives out the parallactic angle, from -90 to 90. Be sure to enter negative hour angles for objects east of the meridian.
If the spectrograph gets hung up some cables, or has other problems, do the following. Turn off the power to the rotator drive mechanism (switch on the east side of the telescope mirror cell, down is off). CTRL-C out of the guide program. Restart the guide program, with "guide". Turn the rotator back on. Move the rotator to a position that allows you to clear the caught cables. Never reboot the guide pc with the rotator power on, or the rotator will run away. (Should now work OK, TG (06/99)
A: Rotate to Angle (70 Max)
Rotates to given angle (between 110 and -110).
S : Set Rotation Speed
This set rotation speed for a M move command.
D : Set Rotation Direction
This set rotation direction for a M move command.
T : Set Rotation Duration
This set rotation direction for a M move command.
M : Make Rotation from S, D, T
This rotates in Direction D at Speed S for Time T.
W : Report Rotator Counts
Show rotator position in potentiometer counts.
P : Rotate To Count
Rotates to potentiometer reading.
Q : return to main menu
For most users, the only command needed is the A command.
This starts up as Off, in case the Realtime System is not running. Only turn this on after Realtime System is up. If you need to exit Realtime System, toggle to off, or guider will "hang-up" waiting for input from Realtime System.
Use this to put the dome away at the end of the night. It will send the dome to 30 degrees azimuth, and turn off track.
This starts in the Off state, and controls whether the dome tracks the telescope. To track telescope, both this and communications must be on.