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2. Antenna Rack (in tower)

xxx

2.1 Tower PC

This is the final motor rack PC: an industrial enclosure with a set of ISA-based cards. (The "extra" temporary PC used in tower in phase 1 will eventually act as a "live" backup spare and it will be equipped with identical boards as the rack PC.) The following equipment will be needed:

  1. An EC-1120 enclosure (FIM 1891); we already have one for motor rack PC.
  2. A CISA-486H CPU card (FIM 1761).
  3. An AMD486DX4-100---120 processor (about FIM 500).
  4. A heat sink without fan for the processor.
  5. A 16MB SIMM RAM memory module (about FIM 650).
  6. A floppy disk drive (about FIM 200).
  7. An 3.5" IDE hard disk drive. We will use some extra drive we already have---capacity is not critical. In the final version the hard disk will be replaced by a non-volatile solid-state flash EEPROM disk such as PC-FD-10 10MB flash disk card (FIM 2337).
  8. A temporary VGA card plus a temporary VGA monitor. The possibility of buying a small monochrome VGA display such as the 9" FT-7112 (FIM 997) will be considered---it would be nicer to handle in tower.
  9. A temporary keyboard; we already have it.
  10. An IK121 Heidenhain RON806 interface card; we already have two of them.

5MHz/1pps/PWM-out/watchdog

xxx new ISA board made in-house (by Jouko :-) with MACH chips...

Quadrature Encoder Input (4 diff.)

xxx digital tachometers (Heidenhain xxx) of the motors

Space for a future secondary mirror position sensor input board

xxx LVDT, optical, ...

16-ch. 16-bit A/D

This is a 16-channel 16-bit A/D converter card such as ET-2816 (FIM 2863) which will read the tiltmeter outputs and a few temperature sensors inside and outside the PC. Adapter card ETD-8125 (FIM 441) plus a D37 cable (ET-10137-1, 1m, shielded, FIM 113) has screw terminals for tiltmeter open ended cable and this has been used in temporary phase 1 installation.

xxx sensors:

  1. Ttilt
  2. x-tilt
  3. y-tilt
  4. T-PC (separate LMxx sensor arrangement (with +/-15V power))
  5. 5*Tfet (from Euro bus motherboard)
  6. 7 spares

16-ch. 12-bit A/D

xxx voltages, currents

  1. 4*28V power
  2. 24V power
  3. 5*Imotor
  4. 5V power, +12V power, -12V power?
  5. brake power?
  6. 2*fan voltage
  7. 0--2 spares

6cn*3*8-bit Digital I/O

An ET-1722B digital I/O card (FIM 919) for:

  1. Absolute ROC412 encoders (2cn*3*8 bit).
  2. 24-bit opto in (1cn*3*8 bit)
  3. Approx. 6-bit direct out
  4. Approx. 8-bit direct out

2.2 Power Supplies

xxx

2.3 Eurocard Bus

xxx

Motherboard

xxx

5*FET-kortti

xxx

FET Driver Board Enable and Watchdog Controller

  1. Interlock GAL
  2. ULN-chip based driver for 24V relays driving motor contactors
  3. Motor contactor relays

xxx connects to both 5M/1pps/PWM/watchdog ISA board and to digital output ISA board.

Secondary Mirror Motor Switcher

  1. Interlock GAL (prevents driving multiple motors at the same time).
  2. ULN-chip based driver for 24V DPDT(?) relays selecting one motor to be connected to one FET board.

xxx connects to digital output ISA board.

Space for secondary mirror position sensor signal processing circuitry

xxx

2.4 Motor Contactors

xxx 4, secondary mirror motors have their own switcher

2.5 Fuses

xxx


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