PDP-11/45 RSTS/E boot problem

Jay Jaeger cube1 at charter.net
Mon Feb 18 15:47:23 CST 2019

On 2/18/2019 3:38 PM, Paul Koning via cctalk wrote:
>> On Feb 18, 2019, at 4:16 PM, Fred Cisin via cctalk <cctalk at classiccmp.org> wrote:
>> On Mon, 18 Feb 2019, Liam Proven via cctalk wrote:
>>> Well that is the thing, of course. I had that with one old IDE disk,
>>> too. It made a terrible ear-piercing high whine that I associate with
>>> a failing disk... but it passed every diagnostic I could throw at it,
>>> so I used it for non-critical stuff and in testbed machines.
>> One of the moxt common causes of a terrible ear-piercing high whine is the spindle contact.  Many old drives had a springy piece that rubbed against the end of the spindle.  
> Then again, I remember our college RS64 (drive for the RC11) which developed a bad motor bearing.  Since the platter is mounted directly on the motor spindle that was a problem.  And it was not under contract, so replacing the motor would have set back the department a substantial sum.  So the DEC FS engineer removed the motor and carried it to Appleton Electric Motor Co., which pulled the old bearing, pressed on a replacement, and handed it back.  Jim reinstalled the motor, all was well.  Didn't even lose any data bits.
> 	paul

Nice of the FE to do that.

The Univ. of Wisconsin CS Department had one of those, but the platter
went bad.  They just flipped the platter upside down and got more use
out of it.

The Univ. of Wisconsin ECE Department also had one - the two machines
were nearly twins.  I *have* *that* one - and it still ran when I tried
it a year or so ago.

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