-Siderostats, housings, neds, periscope mirrors
SUSI's "preferred" baselines.
Baseline Length (m) Stations employed
-Autocol numbers: Beware, if the display on a sidcon
reads ***.000, it's got about a 1 in 1000 chance of being correct, as
sometimes something weird happens and the display resets to ***.000.
Seems only to be a problem with North 4 at the moment, but it is an error
I've [MJI] seen in the past. So, after autocollimating a siderostat,
it is good to write down/type the numbers straight away in case something
like this happens.
Vacuum pipes link the siderostats to the BRT area.
Pumps are in the shed by the e-w vacuum pipes. Key in the usual place.
Pump down the vacuum every few (2-3) days. See the gauges in the NE
corner of the control room. (but S gives an incorrect reading)
There are two pumps, for redundancy. It runs fine, but slower, under one pump.
The pumps have internal valves to prevent oil being sucked into the vacuum but
the clamp-valves provide a backup and extra protection and should be used.
To isolate one pump from the system, in case of failure close the wheel-valve
between the vacuum set and manifold.Ground level pump is the backing pump, the
upper one is the 'Roots blower' (!) The blower cannot operate at high pressure
and there are interlocks to protect it.
There is one control panel per pump.
Turn LH Red switches to on. Middle switches to on. (These usually left on)
Then swivel RH switches to 'on'
Now open clamp-valves to N and S pipes.
**This order ensures nothing is sucked into the pipes!
Pump for ~1-2 hrs.
Then switch off pumps.
One gauge (S) does not read correctly.
If a pump/motor/etc fails isolate it by closing the wheel valve on top.
Here are Bill's instructions:
The SUSI vacuum gauges are thermistor gauges that measure the thermal
conductivity of the residual gas and are very non-linear. They are
very poor at reading high (or extremely low) pressures but are
excellent for pressures in the range of approximately 0.1 to 10 torr
and were chosen for that reason.
The vacuum meter at SUSI has two scales, but only the upper one should
be used. This scale is misleading since it appears to be labeled
"ATM". The actual units of the scale are torr (1 T = 133 Pa or
1/760th of standard atmospheric pressure). The right hand limit of
the scale is 760 T; this is unfortunately marked ATM and wrongly
implies that the scale is in atmospheres, not torr. The height of the
column in a mercury barometer at sea level is approximately 760 mm and
this is the origin of the unit.
Aligning and focussing the apd fibres. [MI]
The field-of-view of the fibres is roughly 20" on the sky. This means in
principle that the alignment is not critical: the full PSF including the
first airy ring is about 10" at 900 nm, giving a maximum tolerance of
about +/- 5" on the sky. This kind of leeway is necessary as the
absolute aiming position of the tip/tilt system is dependant on
dispersion and spectral type (can change by up to 1" or so), and
experience has shown that alignment is not completely stable over
time. The difficult part of aligning the fibres is ensuring that the focus
is also correct, and this cannon be done easily by simply measuring the
amount of starlight coming in to the fibres (although possible in
principle). So, here is another (better?) technique for fibre alignment:
1) Get the MAPPIT laser set up on Peter's fibre-alignement rig (a short
piece of optical rail, hopefully with some/all of the following
components already mounted and sitting in the optics lab). Three
componenets are required: the MAPPIT laser, the fibre holder and a short
focal length lens (one marked '20' on the lens holder is perfect).
2) Take this set up to the roof of the optical enclosure next to the apds.
Unplug one of the fibres from the its apd and plug it into the fibre
3) Align the set up so that the laser is focussed on the fibre head. This
is quite tricky, and you can tell the alignment is correct when the
bright scattered laser spot on the fibre face mostly dissapears.
4) Get off the roof, and check that the laser is bright when it comes out
of the other end of the fibre.
5) Use the mirror 'M' on the red table to reflect this beam accross the
room. The beam edges should diverge by 6 mm over 5 m due to the angular
size of the fibre core. If not, adjust the fibre focus (the large ring to
the back of the fibre mount) until this condition is reached. This is not
particularly accurate, and I'd love it if someone else has a better
idea, but the beam quality isn't really all thaat great...
6) Turn the red table laser on (put appropriate slides etc in place) and
with a roughly 10 mm aperture in, adjust the West-Central OPLC mirrors to
get the laser spots onto the target at the large BRT.
7) Turn this laser off, take mirror 'M'/slides shutters out and align the
beam coming out of the fibre with the same target. Keep the same 10mm
aperture in. The pattern on the targets will not be bright (it's a
divergent beam after all), but should be brightest in the centre. Move the
fibre face using the large knobs on the side and top of the mount to align
the brightest bit of the pattern up with the target. If you can get this
right to within 5mm, then this corresponds to 2'' on the sky and is
8) Repeat with the other fibre.
Things to consider:
1. Check that the coolant level is OK. There is a large screw-cap on
the top of the unit (you need a ladder to inspect this). The fluid
level should cover the cooling coils. If the level is low just add water.
2. The temperature setting might be incorrect. This needs occasional
adjustment due to seasonal changes. It may be set too low. The idea is
to keep the water temperature *slightly* below the ambient temperature
in the instrument enclosure. If it is set too low the cooler has a lot
of work to do and more importantly there is a risk of condensation if
the temperature of the pipes, etc., fall below the dew point.
SUSI has a new GPS clock from Nov 19 2009 - the Krontek KT2000 NTP server.
See Krontek for a datasheet or manual.
The following notes relate to the old clock - no longer required I guess.
The 'Datum TymServe 2100' clock lives in the north electronics rack underneath
the GPS receiver. It should display 3 green lights and the correct time and
WJT has written some comprehensive notes
about time at SUSI, ntp, etc. Read these first.
If the clocks on arthur, peleas, gareth, gaheris are out of sync restart
arthur first then the others.
If the clock is wrong it needs resetting (Bill did this remotely). Just switch
off, wait 5mins, switch on, wait 20mins for all three green light to come on.
Display contrast: press 4 to decrease
press 9 to increase
I set the following options:
1/ IP address=203.015.065.005
2/ Mode=timecode (which makes the clock read its time from the gps)
3/ Set Year=2006
4/ Set Local time offset=+10:00:00
Other settings I did not change are:
1/ Net Mask=255.255.255.000
2/ Default route=000.000.000.000
3/ Host IP address=000.000.000.000
4/ Ethernet address=00a06e040060
Mikes notes are at /mirror/home/mireland/latex/scheduler.tex [or .ps]
My additions to Mike's notes:
a/ load [script file] is now implemented. Click 'go' to run the script.
b/ foto Takes photometry files: north and south and dark. Does all
necessary shutter and siderostat commands.
c/ for fs need to start 200-300 micron below expected position of fringes
to allow pellicle time to move away before scan starts.
d/ Any command can be entered in 'insert command' box. It is executed immediately
or as soon as the present active command is completed.
1. Get the system set for observing: all servers and clients open, optics aligned, sids
2. Go to target star and do a refin alignment with the PHP
3. scheduler & in an arthur window
4. Create a targetname.sched file (or do this before starting alignment). These are
stored in /export/snert/data/schedules.
They should look something like:
acq 3699 acquire an alignment star
align and do align procedure
hrf 3699 now do scans on HR3699 and follow with foto(metry) files
load ../schedules/lcar.sched and now reload this file to repeat
A cycle takes 40-50 mins if everything goes smoothly
ie. ~5-6mins per star
To stop simply hit 'stop' in scheduler whenever you wish.
5. Type load targetname.sched into scheduler
6. 'Single Command' step through acq and align then hit go.
7. The scheduler already knows about
sids, fs parameters, the data directory, file number and scans parameter.
Now it just cycles through the sched file.
8. Note: To clear a .sched file from the scheduler just do:
load ../schedules/empty.sched (which is empty as its name suggests)
and hit 'single command' twice. This saves closing/reopening scheduler.
The following is the old method we used before scheduler ran everything in case you need it.
When scan set ends...
Scheduler starts new astromod
Meanwhile acquire north on StartrackNG. Wait for sids to slew to star then grab and centre
Wobble2 will close loop automatically if 'tasc' is toggled in wobble2 window and pointing is
Acquire south on STNG. Wobble2 closes auto.
Move pellicle to park - but ensure n&s wobble remain closed
s might open when pellicle passes.
Could go to control|widefield to recentre/reclose
Scheduler will search and find fringes
If not found do 'fs start end speed' [set start and end sensibly or -1500 +1500 if
first time, and speed=10 for slow, reliable search.] or try sfo if you know where
the fringes are.
Record log sheet data from Merlin
-Do nfoto, sfoto, dfoto between between each star if necessary
-Keep an eye on the no of scans. There is no obvious 'finished' signal.
-May need to hit 'stop' before 'go' sometimes
Manual photometry - nfoto: smsin, nmsout, maintain tracking on sids and OPLC
dfoto: smsout, nmsout, maintain tracking on OPLC, stop tracking on sids
start set a few seconds after servos open.
Do ~100 scans for each d,b,sfoto set with long scan.
Do ~400 scans for each d,b,sfoto set with short scan???
-Scheduler has time-outs on gaining a sid/wobbler lock and on finding fringes.
But it will just wait for you to manually reacquire on the sids, re-lock the servos
or scan for fringes. After completing each of these manual operations simply hit 'go'
and scheduler will take over from where it paused. Woo hoo!:)
-If fringecon finds false fringes or looses the fringes during a scan then
on fringecon do:
stop (scheduler will remain in "waiting for scan set to end" mode)
start continuous, fs or sfo, start scan
At end of scan scheduler will save as correct run no and continue as normal.
-Wobble2 looses star: go to control|widefield and move sids manually
Siderostats fail to slew to target. Just hit 'Track' in sidcongtk
Each picomotor pair (az+el) has a Driver Module. All, except the reference, come in
Driver pairs with daisy-chained power, eg. drivers 6&7 or 4&5. Then all Driver Modules
have their network connections daisy-chained. There is only one Ethernet Controller which
MUST be switched on last (power board just inside south door from control room with
apd/CCD power). Also need to power on all Driver Modules with a lower value than the
ones you want to use, eg. if using just 8&9 need to power up all from 1-7 as well.
If the ethernet controller is replaced will need to reset its network parameters.
ie its hostname & ip address (see /etc/hosts), ipmode (=stat), gateway
(126.96.36.199) and netmask (255.255.255.0).
WJT has written an application, 'picoset', which sets all the picomotor speeds in one
easy step. See also the document "How to set the picomotor speeds".