This document contains instructions for Paolo on how to switch over from having Martin's PC in charge of the mirror heater system to having the Macintosh in charge of the mirror heater system. These instructions were written by Giles and are based on information obtained during several phone calls that Giles made to Mark and Bob. For reference, these instructions also contain three photos that Paolo sent to Giles on May 29th, 2003.
  1. IMPORTANT: beware of static. take all the usual precautions.

  2. the mirror heating system chassis (fig 3) has four ribbon cables coming out of the back of it.

    • DIO to Martin's PC
    • A/D to Martin's PC
    • DIO to Mac
    • A/D to Mac

  3. NOTE: Mark has pointed out that the two ribbon cables that run from the mirror heating system chassis to Martin's PC do not run *directly*. They actually pass through a break-out box that is located at the rear of the *main* heating system chassis. This is a bit strange, but thats how the cables run.

  4. right now the "DIO to Martin's PC" and the "A/D to Martin's PC" are presumably connected to Martin's PC. The "DIO to Mac" and the "A/D to Mac" are presumably not connected. IMPORTANT: you *never* want to have both computers connected to the mirror heating system chassis at the same time. Also, before you unplug anything, make sure that you label it appropriately so that you know how to hook it back up the way it was originally connected, if necessary.

  5. You told me in late May that the monitor of the Mac is dead. But according to Mark, the Mac monitor will eventually work if you let it warm up for a while. (Maybe you already tried this?)

  6. In case it turns out that the monitor really is *dead* (but please note that Mark says maybe it just takes a long time to warm up) then please note the following: You will find that this monitor has an unusual connector (with some RF connections). So it may be hard to find another monitor with an identical connector. However, Bob L. says that you can use *any* macintosh monitor as long as you plug it into the motherboard instead of into the video card that has the unusual connector. After doing this, you will have to reboot the Mac in order for it to detect the new monitor that is connected.

  7. You will need to know where (on the Mac) to plug in the A/D and where to plug in the DIO. This should be labelled on the Mac, but you have to look carefully. The labelling is on the perimeter of the connector at the back of the Mac, and you have to look "from the side" according to Mark.

  8. The Mac program will start automatically. The Mac will simultaneously display each mirror temperature in two ways: first, in Kelvin, and secondly, as a differential between the mirror and the ambient sensor. Channels 1-4 are the primary, 5, 6, and 8 are the condenser, secondary, and azimuth ring, and 11 is the ambient sensor. If you want to quit the program you have to quit it twice.

  9. The procedure you should follow to make the change is straightforward:

    • A) I assume the following starting configuration: mirror heating system powered up. Martin's PC turned off but still connected. Mac turned off and disconnected. Thus, the mirror current will be 40 Amps (set by current limit).

    • B) unplug the two PC ribbon cables (DIO and A/D) at back of Martin's PC. Make sure to unplug the ones that go to the mirror heating system chassis, not the ones that go to the main heating system chassis. or you can unplug them all if you want. This should be OK as the main heating system will run with no computer. As I said above, label everything that you disconnect so that you can go backwards if necessary.

      • mirror current should go to zero amps at this point, according to Mark

    • C) plug in the two Mac ribbon cables (DIO and A/D) to the Mac

    • D) turn on the Mac

      • after some time to reach equilibrium state, you should see mirror current cycle between 0-10-20 Amps

    • E) stick around MAPO for a while and watch the electronics heater system and watch the mirror heater system to be sure it is all working well.
Fig. 1 - image 004
Fig. 2 - image 005
Fig. 3 - image 007