Date: Tue, 20 Dec 1994 19:06:51 +0800
Subject: SX-50 spectrometers. oscillations at rest
From: B.Robinson@dem.csiro.au (Bruce Robinson)
Cc: B.Robinson@dem.csiro.au, basu@ucs.indiana.edu, brophy@ucs.indiana.edu,
CF_Minerals@cyberstore.ca, chender@umich.edu,
chrisc@sx50.lpl.arizona.edu, chrmille@magnus.acs.ohio-state.edu,
cjwood@dow.com, claudio@quartz.geology.utoronto.ca,
corneliu@wsuvm1.cdc.wsu.edu, croudin@UCSD.EDU,
d_martinez@rumac.upr.clu.edu, dlondon@geoed.gcn.uoknor.edu,
doraism@ucs.indiana.edu, drake@sx50.lpl.arizona.edu,
F.Scott@unsw.edu.au, fnkps@aurora.alaska.edu, garcia@soest.hawaii.edu,
GASP@GUARANY.CPD.UNB.BR, gmckay@snmail.jsc.nasa.gov,
gmorgan@GEOADM.GCN.uoknor.edu, hulse@elepaio.soest.hawaii.edu,
huw@cemmsa.adelaide.edu.au, jcr@quartz.geology.utoronto.ca,
jeronimo@pppg.ufba.br, jinnys@geophysics.rice.edu,
JOAQUIM@pppg.ufba.br, johnf@ice.geology.wisc.edu, jstirlin@emr.ca,
jstor@owlnet.rice.edu, k56@psuvm.psu.edu, maggy@microprobe.esd.mun.ca,
MARCOS@IF1.UFRGS.BR, mbarton@magnus.acs.ohio-state.edu,
mcomerfo@magnus.acs.ohio-state.edu, microprobe@tamu.edu,
miltonp@geophysics.rice.edu, mlw@probe.geo.umass.edu,
mshaf@oregon.uoregon.edu, noso@vtvm1.cc.vt.edu,
npearson@laurel.ocs.mq.edu.au, p01592@psilink.com,
patrick@magic.geol.ucsb.edu, pierce@magic.geol.ucsb.edu,
raudsepp@unixg.ubc.ca, rjs@almaden.ibm.com, rmason@leif.ucs.mun.ca,
rnielsen@oce.orst.edu, robert@starav.geology.gla.ac.uk,
roeske@jade.ucdavis.edu, schiffman@jade.ucdavis.edu,
Shervais@epoch.geol.scarolina.edu, snow@lanl.gov,
steele@geo1.uchicago.edu, summer@probe.geol.scarolina.edu,
teska@sx50.lpl.arizona.edu, valley@ice.geology.wisc.edu,
vicenzi@phoenix.princeton.edu, wagstaff@snmail.jsc.nasa.gov,
wintsch@ucs.indiana.edu, WML5079@geopsun.tamu.edu, wpnash@cc.utah.edu,
yang@snmail.jsc.nasa.gov, bo.johanson@gsf.fi,
David_Sewell.earthsci@muwayf.unimelb.edu.au, Kari.Kojonen@gsf.fi
Status: OR
Best wishes for Christmas and the New Year to SX-50 users.
I have a question about SX-50 spectrometers. Ours sometimes "hunt", or
oscillate continuously, when they should be at rest.
The motor and external gears can keep oscillating backwards and forwards
through part of a revolution at about one cycle per second or a bit faster.
This can be observed by removing the spectro motor heat sink and observing
the gear-wheels by the motor. It can also be detected by hearing the
noises of the oscillations when near the spectro motors.
The oscillation can be stopped by moving the gear wheel a little by hand, or
by moving the spectro to a marginally different position.
I am informed that many SX-50 spectrometers do this, and that it poses no
risk of wearing out the spectrometer mechanical parts. I would like to
check both these assertions.
**************************
Do you know of this phenomenon?, ................
of what causes it?, .............................
if it poses any risk of increasing the wear on the spectrometer bearings,
lead screw etc ?........
.................................................
and how to prevent it happening ?................
Has it happened on your SX?......................
How often?.......................................
***********************************
I would appreciate receiving information, both of occurrences and absences
of spectro oscillations on your SX. I will provide a summary of the
information I receive to anyone who requests it.
The address list used is an alphabetically ordered copy of the most recent
list from John Fournelle (johnf@ice.geology.wisc.edu), plus some others at
the end. I have left my name on the list so if people copy the list I
don't get forgotten. People who are not on the alphabetical list can ask
John to be included so they receive general SX-50 mail.
Chris Capobianco's survey has a list of some 21 SX-50s (and 2 older Camecas)
with names etc to match with e-mail addresses. I have been interested in
the partial results and would encourage other SX owners to fill out Chris'
survey (chrisc@sx50.lpl.arizona.edu).
[We are about to install twin 500MB SCSI disks on our PDP-11. PDP-11 SX
users who want more info can contact me. I hope it works. It will beat the
standard 30MB RD52 disk.]
Regards to all
Bruce Robinson
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| Bruce Robinson |e-mail: B.Robinson@DEM.CSIRO.AU |
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