Cass. Cage Setup

The following steps will test that all the Cass. Cage components of SpectroCam-10 are functioning at their most basic level. The checks are most important on the first night of observing or after cables have been disturbed, but the stepper motor and GSM checks are very important every night. Many of these checks are described in more detail in Setup Procedures.

  1. On the SpectroCam chopping secondary control box in the data room, turn on the Flip Mirror power and set it to the Observe position. Have your assistant in the Cass. cage watch to see that the mirror extends to a 45 deg angle. Turn off the mirror power (important for ground isolation).

  2. Turn on Stepper Motor Controller and Detector Power Supplies (turn on the Clock, PreAmp, and Co-Adder power, in that order. On the power supply, this means turning the switches on from right to left. When turning the electronics off, reverse the order.

  3. Turn on GSM Sensor Power if necessary (it should be left on as much as possible to keep the GSM electronics stable); leave Motor Power off for now.

  4. Check the adjustment of the GSM electronics temperature controller. In equilibrium, the indicated temperature should be about equal to the set temperature (displayed when toggle switch is pushed to right).

  5. Turn on the PC. When the PC boots, it automatically runs PSYS, the SC-10 control program, but it is incorrectly configured to run with the old ezra workstation. After the PSYS program starts automatically, exit it by entering EX from the main menu. Then run PSYS GRB. This is necessary so that the PC will listen for a connection from GRB. If the PC is already running but PSYS is not, just type PSYS GRB to run it. PSYS starts up in ``listen'' mode, waiting for a network connection. Press RETURN to change to menu mode.

  6. Check to be sure the Red LED on the PCLOCK box has gone off and that the yellow one has come on, indicating that the electronics received the serial bits from the PC to initialize the ROM tables.

  7. Check that the Filter and Slit stepper motor odometers (top of dewar opposite the GSM box) agree with the current settings on the PC main menu. They should unless the settings have been changed with the stepper motor power supplies off or if the motors have been turned by hand. Turning them by hand is the easiest way to correct any errors.

  8. On the GSM electronics box on the side of the dewar, set the Manual/Auto switch to Manual.

  9. Turn on the GSM Motor Power.

  10. Turn the Roto-matic CCW until the carousel reaches its stop - the coarse sensor voltage should read 1.25 V. Check the upper stop -- the voltage should be 8.50 V. Correct any errors using the Coarse gain and offset pots according to the procedure in GSM Setup.

  11. Set the GSM Manual/Auto switch to Auto. If a ``clunk'' is heard from inside the dewar, the GSM has hit its hard stop and the motor power should be turned off immediately. The LED indicators on the GSM electronics will go red temporarily as the GSM moves, but should settle on Green. A problem usually indicates that the Coarse and Fine voltages have not been properly set (see above), but it could also indicate that one of the cables is not connected. The GSM is usually reliable, but one should keep an ear open for ``clunks'', and an eye open for the red and green lights whenever manipulating the GSM during instrument setup.

  12. Type IM C from the PSYS main menu to set the instrument mode to camera. This command may also cause the ROM tables to reset and the stepper motors to turn. Make sure the GSM LEDs settle on Green at the end.

  13. Type MF 30 and MS 700 to set the filter and slit wheels to open positions, if they are not there already. You should hear them turning.

  14. Type RO 8 to set the ROM table to 32 Frames/Chop (might require somethings besides 8 depending on ROM table version), and CF 6 to select about a 6 Hz chop frequency.

  15. Type CA from the PSYS main menu to turn on Continuous Acquistion mode. If the GSM is correctly positioned, the array should be brightly lit up. Pressing 1 displays the first chop buffer, 2 the 2nd chop buffer, and 3 the difference between them (1 - 2). The signal will probably be off scale (buffers 1 and 2 saturated and the difference between them 0) if the pick-off mirror is not extended or if the mirror covers or dome are closed. If there is no signal at all, check that the filter and slit wheels are not in the block position. If there still isn't any signal, it is probably time for an experienced operator to hook up an oscilloscope to the signal outputs on the PClock box and use the Pixel Step PS commands to get the signal on the detector. Small offsets can be corrected more easily from the GRB workstation in the data room.

  16. Press the ESC key to exit Continuous Acquistion mode.

  17. If everything is OK, type MF 10 to set the filter wheel to the block position (to keep the detector from saturating when powered up), then EX followed by PSYS GRB. The screen should display ``SpectroCam-10...'' repeatedly as the PSYS program goes back into listen mode.

  18. Turn off the PC monitor (switch on right side) so its light won't flood the Centerfield and Offset Guider cameras.

  19. It is best to set the Cass. Ring to the desired rotation angle (nominally about 90 deg) before leaving the cage.