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User name R. Michaels
Log entry time 08:13:40 on June 26, 2010
Entry number 328350
keyword=how to fix spot++
Here's some advice on how to fix spot++ in case I'm not around.
I think any of the experienced Hall A people can do these jobs.
BTW, you might survive without it since: a) raster size can be measured
with HARP; and b) average position is measured with striplines, whose
values are in EPICs and recorded in our datastream. But maybe that's
not good enough for some reason ... someone else to decide.
To fix spot++, I think you need to do the following. (This applies
to both HRS, but since you'll eventually connect the two HRS you only
really need to fix one side. The R-HRS is presumably still intact but
the DAQ there doesn't work yet because of a bad RS485 cable.)
The to-do list:
I. Restore pulser trigger T8. At the moment the 1024 Hz pulser goes
to the 24th channel of the normalization scaler, so may put a copy of
it to T8 as usual.
II. Restore cabling to Fastbus.
a) See black cable for ADC, possibly still dangling near crate unless
the experiment "cleaned it up" (removed it) as they have been apt to do.
b) Cable origin is from the offset/attenuator boards which are in NIM
or VME, located on the right-side as you climb the bottom platform.
c) Need a narrow gate (50 - 70 nsec) for that ADC. Can tell it's ok
from a pedestal run: should see signals that are not saturated (4096).
d) Turn off pedestal suppression for those channels. (need zero's as
entries in ped3.dat or ped4.dat) If you never do a pedrun, entering
the zero's by hand is sufficient; otherwise the pedrun machinery needs
to be modified so that the zero's get written when pedestals are
generated. Too much to explain here, but several people know this.
e) Unless you happen to use the same slot and channel as before, you'll
need to modify the database. Type "which spot_L" to find out where the
software is, probably ~adaq/rastersize/LeftHrs and then there's a DB
directory there. Control the detmap in the standard way (Note, spot++
is an application of the Podd analyzer).
I think that will do it. If you see non-saturated and non-zero raw ADC
data from a beam-off run, you should be ready for beam-on.
You'll want to do a bulls-eye scan with beam to check the calibration.
And corroborate with a HARP scan too.
A copy of this log entry has been emailed to: camsonne, bogdanw, vasulk, aserg, rom