User name R. Michaels
Log entry time 11:48:17 on March 7,2007
Entry number 195057
keyword=raster current on R-armThe raster current on L-arm has a big spike at the left edge,
it is probably hitting the pedestal area of the ADC. We can
adjust the offset box to put the signal further up. See fig 1.
Meanwhile on the R-arm it looks more flat (see fig 2).
Both ADCs see periodic spikes in the ADC. This is as if there
were a bad bit in the ADC (but then it's not likely to be in both).
Or as if there is a beat frequency to the trigger (but then it's
also seen with a random trigger). So I don't know what causes
the spikes but we can check on a scope. Note, the spikes in the
BPMs at middle of the target go away when you use a pulser trigger,
so I think that was at artifact of the physics trigger. Also I think
these spikes in current were always there, i.e. not new.
FIGURE 1
FIGURE 2
