User name paschke
Log entry time 15:37:20 on June21,2004
Entry number 126528
keyword=How to Fix bpm12 when it goes bad
Sometimes bpm12 readback goes bad. This happens most often when beam
is coming on and off, or when we are changing current a lot. This
has been identified as a minor (and transitory) FastFeedback
misconfiguration, which can be fixed easily.
When bpm12 starts to look funny (either saturating in our ADC readout,
or having an absurdly small width) call MCC and utter the following
"There is a DAC failure on the Hall A FastFeedback. Please do a gain search."
The ops can fix the problem right away, very easily. They usually
catch this error themselves and solve the problem, but occasionally it
escapes their attention. Now that we know the magic words, we can