From: news@alderson.users.panix.com   
      
   =?UTF-8?Q?Arne_Vajh=C3=B8j?=  writes:   
      
   > On 12/1/2025 6:56 PM, Rich Alderson wrote:   
   > > =?UTF-8?Q?Arne_Vajh=C3=B8j?=  writes:   
   > >> On 12/1/2025 1:02 PM, Scott Dorsey wrote:   
   > >>> There are many devices that should be preserved in working condition so   
   that   
   > >>> new generations should see how they worked when they were new and   
   experience   
   > >>> them working.  The RA81 should be left in the rack broken, so that new   
   > >>> generations can see how they were when they were new.   
   > >   
   > >> RA81's and RA82's on a 8650.   
   > >   
   > >> The RA82's were okay, but the RA81's crashed frequently. DEC field   
   > >> service knew that site very well.   
   > >   
   > >> I have been told here that there were a manufacturing problem with   
   > >> RA81's and when the problem got fixed they stopped crashing all the   
   > >> time.   
   > >   
   > > You've got the RA81 and RA82 backwards.  We had RA81s on a CI cluster at   
   > > Stanford, and they were pretty solid.   
   > >   
   > > RA82s were not available for the 36 bit systems, but we heard about them   
   from   
   > > our DEC FEs.   
   >   
   > I could easily remember it wrong - it has been a long time.   
   >   
   > But a search in c.o.v confirmed that it was the RA81's.   
   >   
   > 2003 post:   
   >   
   >    
   > The problem with the RA81's wasn't that the drives were really flaky --   
   > there were some early data and noise problems ECO's out under warranty   
   > early on -- but that the glue that held the HDA filter was substituted   
   > without a close look at the specifications of the glue.   
   >   
   > The substituted glue on HDA's at Rev F (IIRC) would liquify at warm   
   > temperatures and flow to the bottom of the HDA and crash head 13   
   > into the bottom platter every time.   
   >    
   >   
   > 2021 post:   
   >   
   >    
   > The early RA81s had a problem where the heads would "unglue" from the   
   > actuator and totally trash the disk.   
   >   
   > DEC actively hunted out and replaced those original drives. The   
   > replacement RA81s were good and ran forever.   
   >    
      
   Odd.  That's exactly what I remember about the RA82!   
      
   --   
   Rich Alderson					  news@alderson.users.panix.com   
         Audendum est, et veritas investiganda; quam etiamsi non assequamur,   
   	  omnino tamen proprius, quam nunc sumus, ad eam perveniemus.   
   									--Galen   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)