Log entry time 19:30:52 on November13,2007

Entry number 214339

keyword=LHRS BPM Part II

I looked at the raw BPMA antenna signals starting from pre-access on
November 7 through November 12 to check the differences in the
various unplanned configurations. Here is the summary:



Period     Antenna 1     Antenna 2     Antenna 3     Antenna 4

---------------------------------------------------------------

Before       3096          3570          3565          4156

Access 2     5839        Saturated     unplugged       3960

Access 3     6043          7057          6275          4017

Access 4     2965          3569          3545          4013

For the Access 2, 3 and 4 periods, I averaged the raw ADC signals
together for a handful of runs, whereas, I choose only one run from
the before period (2074). The "Before" period is before the day shift
controlled access on Nov. 7th, when everything was working fine. The
"Access 2" period is after the owl shift access on Nov. 9th. The
"Access 3" period is after the day shift access on Nov. 9th, and the
"Access 4" period is after the swing shift access on Nov. 12th, when
everything should be working fine again.

A few notes:

1) Luckily, BPMA antenna # 4 was unaffected by this since it was not
unplugged and it was plugged into a different attenuator than the
other three antennas.

2) The ratio of "Access 3/Before" = 2.04 (antenna 1), 1.98 (antenna 2)
and 1.77 (antenna 3). The signal looks to be about a factor of
two smaller than the original attenuator box. This should be due
to a combination of the attenuation and offset settings.

3) The antenna # 2 and 3 signals are not recoverable for run
numbers 2111 to 2123 for BPMA. The BPMB antenna # 3 signal is
also not recoverable since this cable was also unplugged during
this period.

User name V. Sulkosky

Log entry time 19:30:52 on November13,2007

Entry number 214339