SPEAR LLRF Station Hardware Setup Procedure


  1. Using the station hardware list as a guide, install each VXI module into the proper slot.  Make sure the crate is not powered when removing/installing modules.  The power switch is on the lower right on the front of the VXI crate.

  2. Connect the Ethernet cable to the Ethernet port of the Kinetics Systems V152-AB41 MVME2400 processor in slot 0.

  3. Connect the terminal server cable to the slot 0 processor.  On a linux machine, create a terminal server connection using the alias iocrf.  The terminal session is used to allow setting the proper boot links for the processor to initialize.  It also displays the latest error messages for convenience.

  4. See SPEAR RF IOC for instructions on setting up the processor board.

  5. Connect the serial link to the Allen Bradley scanner module in slot #1.

  6. Connect the multi coax Phoenix connector to the front of the clock module.  Make sure that the 2 mounting screws are installed to prevent the connector from becoming loose.  The signals on this connector from top to bottom are as follows:

    Fiducial input - 0 - -1V signal originating from Wenzel Associates Low Phase Noise Frequency Synthesizer and buffered by a Clock/Sync Distribution Chassis - one period per turn (low for 520 ns, high for 260ns) - 1.2804 MHz

    LO output #1  - 471.2 MHz local oscillator output for IQA detector slot #7    approx. +13 dBm output

    LO output #2  - 471.2 MHz local oscillator output for IQA detector slot #9    approx. +13 dBm output

    LO output #3  - 471.2 MHz local oscillator output for IQA detector slot #11  approx. +13 dBm output

    LO output #4  - not used - disconnected in module to improve 471.2 MHz to 476.3 MHz isolation

    RF output #1  - 476.3 MHz RF output for RF processing module in slot #4   approx. +15 dBm output

    RF output #2  - 476.3 MHz RF output for IQA detector slot #7, channel 6  - used for diagnostics

    RF input          - 476.3 MHz input originating from Wenzel Associates Low Phase Noise Frequency Synthesizer and buffered by the Link Pass Thru module, approx. +10dBm nominal

  7. Connect the RF output #1 from the clock module in slot #2 to the 476.3 MHz input on the RF Processing (RFP) module in slot #4. An attenuator is required to set the input power level to +4dBm. Use a RF power meter to determine the exact value of attenuation required. The SMA connector should be snug but do not over tighten.  The 476 OK LED on the RF module should turn green when the RF is connected.

  8. Connect the 4 cavity probe inputs from the 30dB directional couplers at the top of the shielded rack to the cavity 1-4 input on the RFP module. Note the cable labels to help identify the proper location of each cable. Verify that the four jumpers visible through the front panel are set to 4 cavity.

  9. The RF output from the RFP module in slot #4 must be connected to the input of the 120 Watt drive amplifier. An attenuator is required to  properly scale the baseband drive level in the module for proper operating point and sufficient dynamic range. Start with the attenuator value used on a neighboring station.  A lower value allows more dynamic range, a higher value limits drive power under saturated RF feedback conditions.  The input to the 120 Watt amplifier is located on the rear of the amplifier.

  10. Each IQA detector module requires a 471.2 MHz local oscillator signal from the clock module (see 6 above).  No attenuator is required on the LO cable.  The SMA connector should be snug but not over tightened.

  11. There are 8 RF inputs on each IQA detector module which must be connected to the correct RF signal. The individual cables are labeled but in case of confusion the channel assignments can be read from the Phase/Powers EPICS display.  Again the SMA connector should be snug but not over tightened.

  12. The Arc/interlock module (AIM) in slot 12 has 2 ribbon cables which must be connected to the  front panel of the Arc/interlock chassis.  They are different size cables so it is obvious where they connect.

  13. The Arc chassis has inputs on the rear panel.  Each arc channel has a receive and a transmit connector (for online testing).  The 4-cavity station arc channels are split to protect both the air and vacuum side of each cavity window.  The channel assignments are:

    Arc channel 1 - klystron output window

    Arc channel 2 - circulator ferrite

    Arc channel 3 - not used

    Arc channel 4 - 4-Cavity Station cavity A, 2-Cavity Station cavity A vacuum side

    Arc channel 5 - 4-Cavity Station cavity B, 2-Cavity Station cavity B vacuum side

    Arc channel 6 - 4-Cavity Station cavity C, 2-Cavity Station cavity A air side

    Arc channel 7 - 4-Cavity Station cavity D, 2-Cavity Station cavity B air side

  14. The Arc chassis has an RF input to monitor klystron output power and a multi pin connector to send the detected RF voltage out to the Allen Bradley system to be used in the klystron collector power protection.  Make sure these rear panel connections are established.

  15. The Arc chassis also has a series of on/off fiber optic circuits which interface to the local panel and the HVPS.  Make sure these connections are established (from left to right on rear of Arc chassis):

    Heart Beat - from local panel fiber optic transmitter U21 - used to ensure Allen Bradley PLC is alive and well

    A/B Summary - from local panel fiber optic transmitter U22 - RF Allen Bradley summary

    Fault Reset - to local panel fiber optic receiver U16 - sends fault reset signal to RF Allen Bradley system

    Filament Timeout - to local panel fiber optic receiver U15 - sends filament timeout bypass to RF Allen Bradley

    Beam Abort - to local panel fiber optic receiver U10 - sends VXI beam abort signal to RF Allen Bradley

    HVPS On - to local panel fiber optic receiver U12 - sends HVPS ON request to RF local panel

    Solenoid On - to local panel fiber optic receiver U13 - sends EPICS online/offline status to RF Allen Bradley

    Filament On - to local panel fiber optic receiver U14 - sends filament ON request to RF Allen Bradley

  16. At this point make sure the VXI crate is plugged into the AC socket in the rear of the shielded rack.  Verify that the 120 Watt drive amplifier is also connected to the AC circuit.  It has its own internal thermal protection.

  17. Connect the RF output from the 120 Watt amplifier (rear panel) to the RG-214 jumper which leads to the type N feed through labeled klystron drive.  Also connect the monitor cable for the drive power to the forward output coupler on the rear of the amplifier.  Install a type N load on the reflected monitor port (also on the rear of the amplifier).  When all connections on the amplifier are complete, turn on the amplifier AC switch located on the amplifier front panel.

  18. Turn on the VXI crate power (lower right of the crate).  Processor should begin to boot.  You can monitor progress on the local iocrf terminal server session.  If the processor fails to boot you can use a pointed object and manually reset the processor by asserting the recessed reset button on the processor front panel but this should not necessary.

  19. After a few minutes the station's EPICS display should come alive and you are ready to proceed with the Station Configuration Procedure.

Contact:  Stephanie Allison
Last Modified:  Thursday, Jul 11, 2008