You first release the latche(s) behind the front panel as has been noted
(either depressing the one in the middle with a screwdriver or releasing the
two hex latches).  Lift the entire front panel. (Depending on the the
vintage, you may want to use an adjustable wrench or visegrip on the shaft
of the gas spring to keep the cover from dropping on your head.)  Note also
that if you have the RA81 case pulled out far enough to raise the cover, you
should also pull out the cabinet stabilizing foot to keep the whole thing
from tipping over.  On the top of the head disk assembly near the front you
will find a white plastic lever about 3" long.  When rotated so that the
lever points to the right, the disk heads are unlocked.  There is also a
lever mechanism along the right edge of the cabinet which engages/disengages
the motor/drive belt.  There may also have been some shipping brackets to
prevent movement of the entire head/disk assembly depending on how carefully
the unit was deinstalled
----- Original Message -----
From: "nierveze" <alain.nierveze@radio-astronomie.com>
To: <port-vax@netbsd.org>
Sent: Monday, November 12, 2001 3:45 AM
Subject: Re: RA81 problems, someone with a service manual can help?


>
> hello,
> there is a lever with two positions lock/unlock on the hda,look on what
> position it is
> must be on unlock (but how could it set itself to lock position ?
> it is a mecanism to stop the heads when transporting the hda,I think it is
> only a manual
> mechanism not automatic ).Maybe there is a problem on the microprocessor
> module.
>
> We have the ek-ora81-sv-001,would it help you?If yes send your address
> by e-mail
>
> regards
> *************************************************************
> Florence et Alain Nierveze
> 492 Allée Montesquieu
> 33290 Le Pian Medoc
> FRANCE
> ************************************************************
> E-mail : nierveze@radio-astronomie.com
> Web  : www.radio-astronomie.com
> -----Message d'origine-----
> De : Gunther Schadow <gunther@aurora.regenstrief.org>
> À : classiccmp@classiccmp.org <classiccmp@classiccmp.org>;
> port-vax@netbsd.org <port-vax@netbsd.org>
> Date : lundi 12 novembre 2001 03:40
> Objet : RA81 problems, someone with a service manual can help?
>
>
> >Hi,
> >
> >today I moved the RA81 from the garage down into the Laundry/Computer-
> >Room in the basement. Thanks to my straps and a hydraulic car jack-
> >stand I was actually able to install it in my TU81+ cabinet without
> >breaking my back or getting squished underneath the drive :-). It
> >looks really cool in the TU81 rack. I powered it up and though no
> >lights at these push-buttons come on, I could test it quite far.
> >Thanks to Will Kranz' abridged service manual
> >
> >http://www.conknet.com/~w_kranz/pdp11/RA81.HTM
> >
> >I knew what I could do with the terminal and that CTRL-C will
> >get it going (not CTRL-Z like with the TU81+) and after running
> >diagnostics once, I could actually spin up the drive. Just
> >seeking seems not to work.
> >
> >Spun up diagnostigs gets the error
> >
> >terminal plugged in, 300 b/s, 8 bit, 1 stop no parity
> >
> >þ
> >^C
> >
> >CTRL-C gets a prompt
> >
> >  RA81> EUR^C
> >
> >  RA81> EUR
> >
> >turn serial port to 7 bit instead of 8 removes the junk
> >
> >  RA81>
> >
> >  RA81> RUN DIAGNOSTICS
> >
> >%RA81-COMPLETED TEST:DIAG SUBTEST:02
> >%RA81-COMPLETED TEST:DIAG SUBTEST:01
> >%RA81-COMPLETED TEST:DIAG SUBTEST:07
> >%RA81-COMPLETED TEST:DIAG SUBTEST:08
> >%RA81-COMPLETED TEST:DIAG SUBTEST:0B
> >%RA81-COMPLETED TEST:DIAG SUBTEST:03
> >%RA81-COMPLETED TEST:DIAG SUBTEST:0D
> >%RA81-COMPLETED TEST:DIAG SUBTEST:19
> >%RA81-COMPLETED TEST:DIAG SUBTEST:1B
> >%RA81-COMPLETED TEST:DIAG SUBTEST:1C
> >%RA81-COMPLETED TEST:DIAG SUBTEST:1D
> >%RA81-COMPLETED TEST:DIAG SUBTEST:1E
> >%RA81-COMPLETED TEST:DIAG SUBTEST:1F
> >%RA81-COMPLETED TEST:DIAG SUBTEST:20
> >
> >this was diagnostics spun down, everything successful! Now
> >I push the RUN/STOP switch in and there comes the sound of
> >the drive spinning up, really impressive!
> >
> >  RA81> FRONT PANEL FUNCTION IN PROGRESS
> >
> >then this message comes and a long time nothing, finally:
> >
> >%RA81-TEST: SUBTEST:1B  ERROR:50  UNIT:001
> >%RA81-FRU-SLAVE RESPONSE FAIL- SERVO,MICRO
> >
> >not knowing what else to do I do diagnostics again in spun
> >up mode
> >
> >  RA81> RUN DIAG
> >
> >%RA81-COMPLETED TEST:DIAG SUBTEST:02
> >%RA81-COMPLETED TEST:DIAG SUBTEST:01
> >%RA81-COMPLETED TEST:DIAG SUBTEST:07
> >%RA81-COMPLETED TEST:DIAG SUBTEST:08
> >%RA81-COMPLETED TEST:DIAG SUBTEST:0B
> >%RA81-COMPLETED TEST:DIAG SUBTEST:03
> >%RA81-COMPLETED TEST:DIAG SUBTEST:19
> >%RA81-TEST:DIAG SUBTEST:1B  ERROR:50  UNIT:001
> >%RA81-FRU-SLAVE RESPONSE FAIL- SERVO,MICRO
> >
> >  RA81> RUN SEEK
> >
> >ENDING CYLINDER? 1000
> >
> >GROUP? 10
> >OPERATION FAILED
> >
> >
> >  RA81> RUN RECAL
> >
> >%RA81-TEST:RECA SUBTEST:2A  ERROR:50  UNIT:001
> >%RA81-FRU-SLAVE RESPONSE FAIL- SERVO,MICRO
> >
> >At no time I heard any seeking activity. Will's service manual page
> >says this:
> >
> > > D.28 TEST 1B (SERVO PLO TEST)
> > > This test checks the servo module PLO circuitry.
> > > Errors associated with this test are: 50, 7B, C6, FO to FE.
> >
> >I don't see any system fault code on the led bits in the front of
> >the controller board with the hood open after the E7 "test in
> >progress" status byte is cleared. (So I do see the blinkenlights,
> >just there is no fault code besides the error message on the
> >service terminal.
> >
> >Error 50:
> >
> > > 50   Ensure that positioner motor lock is in the unlock
> > >      position. If OK, then replace servo module,
> > >      microprocessor module
> >
> >So, sounds like there is once chance for me: to find this
> >"positioner motor lock" and move it into the unlock position.
> >However, I have no idea how to do that? It sounds reasonable
> >that this thing may be locked for transport, I sure hope
> >so, because otherwise all my moving and installing this
> >thing would have been in vain.
> >
> >any help with this is appreciated. Not that I depend on the
> >RA81 for operation, but I've got it and I believe in having
> >a VAX collection with 100% functional stuff.
> >
> >regards
> >-Gunther
> >
> >
> >PS: Anyone having dead RA81's for parts? Anyone has spare
> >SDI bulkheads? I need one or two 2- or 4- port bulkheads
> >for the RA disks outside the SA600 cabinet.
> >
> >
> >--
> >Gunther Schadow, M.D., Ph.D.                    gschadow@regenstrief.org
> >Medical Information Scientist      Regenstrief Institute for Health Care
> >Adjunct Assistant Professor        Indiana University School of Medicine
> >tel:1(317)630-7960                         http://aurora.regenstrief.org
> >
>