New subject: TBBS for CP/M ?

20 Apr 2007

...

Subject: Micropolis 1355 ESDI hard drive "sticky bumpers" Fixed!
   From: "Andy Piercy" <andy.piercy at gmail.com>
   Date: Fri, 20 Apr 2007 13:46:37 +0100
     To: cctalk at classiccmp.org

Allison,

Well hats off to you, it worked! 
The advantage of being exDEC.  I had a lot of stuck rd53s and built up
a lab MicroVAX system by fixing a few when noone could get their hands on
stuff (budgets).  I figured they were officially dead and the worst that 
could happen is they get deader.   I'd scrounge bits and peices and trade
RD53s as needed with other groups to get the needed bits.  My boss was 
surprized when a request for node address came back to her for approval 
for a system under my desk.  When she saw the BA123 with 3 RD53s and a 
RD54 she wanted one, I produced that one in about a week.  Getting her the
19" color monitor was tricky though. ;) 

...
 I have now fixed the faulty internals of the two faulty
Micropolis hard
drives by teasing out the black gooey mass that use to be the head park
rebound bumper / end stops for each drive.

They had turned into a black sticky mush and as you correctly identified
were holding the heads from un-parking.

However one of the logic board has also gone faulty so if anyone has a spare
faulty drive they would be willing to part with the hopefully working bottom
logic board please contact me. 
You will likely have success finding a board or another complete drive 
(with stickies).  Now that you know how to fix them you may find an excess
of the drives results. ;)

Allison

...

Drive type:                               Micropolis 1355 ESDI 5 1/4 full
height (144 MB)
Part no.                                   900568-11-4a
Faulty PCB part number:          101942-04-3 B2
Eprom fitted:                            800140-03-0 (But this is just for
ref)

Many thanks,

Andy. 