Hours on the Linac 7835 Power Amplifiers

Last data update: Sun Nov 22 05:30:10 CST 2009

Station Tube S/N Gradient Filament A Hours Days Fraction of
median* life
1 BA1 1 6398 9937 414 0.63
2 BA2 0.98 6727 10906 454 1.01
3 AZ4R1 0.99 6991 7751 322 0.72
4 BA3 0.96 6833 10000 416 0.93
5 BA4R1 0.99 6794 7986 332 0.74
7 BA6 -0.01 5 819 34 0.07

*Median lifetime for tubes is about 10750 hours (15750 for tank 1). This is 447 days (656 for tank 1).

Spare 7835 Inventory

  • N27R8, 62 hours
  • A20R8, 219 hours
  • A1R9, 388 hours
  • C2R7, 0 hours
  • A30R7, 0 hours
  • BK1, 214 hours
  • N49R7, 474 hours
  • BA11, 0 hours
  • BV7R1, 0 hours
  • BK3R2, 0 hours
  • BV6R1, 0 hours
  • BV8R1, 0 hours

    • 7835 Delivery Schedule

    Regular Deliveries
    TubeDeliveryStatusOwner
    BK1 Unknown Returned to Burle 12/05 FNAL
    New 12/06 FNAL
    		Bulk Order of New Tubes (Feb, 2005)
    Order completed on April 4, 2006
    All delivery dates are estimates
    Last modified: Tue Sep 20 09:00:55 CDT 2006

    The following tubes are getter-less:

    Klystron Hours

    ModuleMnf*S/NHoursDaysYearsInternal
    Vacuum
    uA
    0 V L122 131534 5480 15 0.20
    V V L113 135253 5635 15.4 0.00
    1 L 0005R1 46153 1923 5.2 0.01
    2 L 0004 134256 5594 15.3 0.00
    3 L 0006 118625 4942 13.5 0.04
    4 L 0016 48992 2041 5.5 0.04
    5 L 0007 137451 5727 15.6 0.01
    6 L 0013R1 74919 3121 8.5 0.31
    7 L 0015 119606 4983 13.6 0.42
    D V A21 117201 4883 13.3 0.00

    *Mnf = "Manufacturer", V is Varian VKP-7955 and L is L3 (Litton) L-5859

    Spare Klystron Inventory

  • V_K107, 0 hours
  • V_L026Z, 8086 hours
  • L_0003, 2194 hours
  • L_0010, 72076 hours
  • L_0011, 37163 hours
  • L_0017, 0 hours
  • L_0018, 0 hours
  • L_0019, 0 hours
  • L_0020, 0 hours
  • L_0021, 0 hours

    • The last two klystron to fail were in KRF4, S/N 0009, at 83278 hours on November 14, 2003 and in KRF1, S/N 0002R1, at 29345 hours, on December 23, 2003. These klystrons failed due to severe vacuum problems. We have replaced two other klystrons since 1993 (at KRF1 and at KRF6).

    Of all the tube that have failed, 5 have failed offline with essentially no hours on them (due to vacuum problems). Of the failed tubes with significant hours, they had 83278 (S/N 0009), 64000, 43800, 37000, 29345 (S/N 0002R1) and 27000 hours when they failed..

    The delivery schedule for the klystrons being rebuilt is as follows:

    TubeDeliveryComments
    0014 September 2005
    0008 October 2005
    Schedule Last modified: Fri Aug 26 13:48:44 CDT 2005

    Last data update: Sun Nov 22 05:30:10 CST 2009