19 Sep
2021
19 Sep
'21
3:58 p.m.
Ok, so out of the basement came a Micrapolis 1325 (the old Dec RD53
disk) with what appears to be stuck heads. Rotor tries to move under
power but can only take out slack. Will move backwards a bit.
Is this stuck head, and what would be the best way to free it? The
reason I'm asking is this disk had a SA1000 adapter mounted under it so
I am pretty sure it was a PERQ disk. Which means data may be priceless.
And of course it's stuck.
Thoughts?
CZ
19 Sep
19 Sep
7:18 p.m.
20+ years ago, I remember people talking about disassembling these to fix the issue. I?ve
never tried. Though I have one or two that might benefit from is. If the CLASSICCMP
archives from ?97-2000 are online, I?d recommend running a search against them.
Zane
On Sep 19, 2021, at 3:58 PM, Chris Zach via cctalk
<cctalk at classiccmp.org> wrote:
Ok, so out of the basement came a Micrapolis 1325 (the old Dec RD53 disk) with what
appears to be stuck heads. Rotor tries to move under power but can only take out slack.
Will move backwards a bit.
Is this stuck head, and what would be the best way to free it? The reason I'm asking
is this disk had a SA1000 adapter mounted under it so I am pretty sure it was a PERQ disk.
Which means data may be priceless. And of course it's stuck.
Thoughts?
CZ
8:58 p.m.
I have simply opened and physically moved the disk counter clockwise a
turn, in a clean dust-free place. Or try putting in an oven on warm for 3
minutes a side, all four sides to loosen the grease. Might sound crazy but
these have worked for me before
Bill
On Sun, Sep 19, 2021, 10:18 PM Zane Healy via cctalk <cctalk at classiccmp.org>
wrote:
20+ years ago, I remember people talking about
disassembling these to fix
the issue. I?ve never tried. Though I have one or two that might benefit
from is. If the CLASSICCMP archives from ?97-2000 are online, I?d
recommend running a search against them.
Zane
On Sep 19, 2021, at 3:58 PM, Chris Zach via
cctalk <
cctalk at classiccmp.org> wrote:
Ok, so out of the basement came a Micrapolis 1325 (the old Dec RD53
disk) with
what appears to be stuck heads. Rotor tries to move under power
but can only take out slack. Will move backwards a bit.
Is this stuck head, and what would be the best way to free it? The
reason I'm
asking is this disk had a SA1000 adapter mounted under it so I
am pretty sure it was a PERQ disk. Which means data may be priceless. And
of course it's stuck.
Thoughts?
CZ
9:17 p.m.
I had suggested a hair-dryer, as recommended circa 20 years ago for drive
"stiction" after disuse. It seems that worked.
On Sunday, September 19, 2021, 08:58:57 PM PDT, Bill Degnan via cctalk <cctalk at
classiccmp.org> wrote:
I have simply opened and physically moved the disk counter clockwise a
turn, in a clean dust-free place.? Or try putting in an oven on warm for 3
minutes a side, all four sides to loosen the grease.? Might sound crazy but
these have worked for me before
Bill
On Sun, Sep 19, 2021, 10:18 PM Zane Healy via cctalk <cctalk at classiccmp.org>
wrote:
20+ years ago, I remember people talking about
disassembling these to fix
the issue.? I?ve never tried.? Though I have one or two that might benefit
from is.? If the CLASSICCMP archives from ?97-2000 are online, I?d
recommend running a search against them.
Zane
On Sep 19, 2021, at 3:58 PM, Chris Zach via
cctalk <
cctalk at classiccmp.org> wrote:
Ok, so out of the basement came a Micrapolis 1325 (the old Dec RD53
disk) with
what appears to be stuck heads. Rotor tries to move under power
but can only take out slack. Will move backwards a bit.
Is this stuck head, and what would be the best way to free it? The
reason I'm
asking is this disk had a SA1000 adapter mounted under it so I
am pretty sure it was a PERQ disk. Which means data may be priceless. And
of course it's stuck.
Thoughts?
CZ
11:13 p.m.
That is what fixed it, hair dryer blowing around the unit. I stayed away
from the circuit boards and just kept moving to
different places. I
thought a head was sticking, but it finally started to move a
bit so it
might have been a really gummed bearing. Or #3 head was stuck and
loosened, most of the errors are on that head.
Running it through the MFM tool got all but 200 or so sectors on the
first pass, most errors were on head 3 but tapered off after cyl 500.
Seems like a normal copy of Accent, no special information so it might
not be worth taking the world apart to get it working.
Thanks everyone. Back to
On 9/20/2021 12:17 AM, Jonathan Stone via cctalk wrote:
I had suggested a hair-dryer, as recommended circa
20 years ago for drive "stiction" after disuse. It seems that worked.
On Sunday, September 19, 2021, 08:58:57 PM PDT, Bill Degnan via cctalk <cctalk
at classiccmp.org> wrote:
I have simply opened and physically moved the disk counter clockwise a
turn, in a clean dust-free place.? Or try putting in an oven on warm for 3
minutes a side, all four sides to loosen the grease.? Might sound crazy but
these have worked for me before
Bill
On Sun, Sep 19, 2021, 10:18 PM Zane Healy via cctalk <cctalk at classiccmp.org>
wrote:
20+ years ago, I remember people talking about
disassembling these to fix
the issue.? I?ve never tried.? Though I have one or two that might benefit
from is.? If the CLASSICCMP archives from ?97-2000 are online, I?d
recommend running a search against them.
Zane
On Sep 19, 2021, at 3:58 PM, Chris Zach via
cctalk <
cctalk at classiccmp.org> wrote:
Ok, so out of the basement came a Micrapolis 1325
(the old Dec RD53
disk) with what appears to be stuck heads. Rotor tries to move
under power
but can only take out slack. Will move backwards a bit.
Is this stuck head, and what would be the best
way to free it? The
reason I'm asking is this disk had a SA1000 adapter mounted
under it so I
am pretty sure it was a PERQ disk. Which means data may be priceless. And
of course it's stuck.
Thoughts?
CZ
21 Sep
21 Sep
1:35 a.m.
I have about a dozen or so 1325,1335, and 1355 drives here, also some
earlier ones (some have the DEC label) RD50, 51,52, and even a few 54s. If
anyone is interested, please contact me off list.
Thanks, Paul
On Mon, Sep 20, 2021 at 1:14 AM Chris Zach via cctalk <cctalk at classiccmp.org>
wrote:
That is what fixed it, hair dryer blowing around the
unit. I stayed away
from the circuit boards and just kept moving to different places. I
thought a head was sticking, but it finally started to move a bit so it
might have been a really gummed bearing. Or #3 head was stuck and
loosened, most of the errors are on that head.
Running it through the MFM tool got all but 200 or so sectors on the
first pass, most errors were on head 3 but tapered off after cyl 500.
Seems like a normal copy of Accent, no special information so it might
not be worth taking the world apart to get it working.
Thanks everyone. Back to
On 9/20/2021 12:17 AM, Jonathan Stone via cctalk wrote:
I had suggested a hair-dryer, as recommended
circa 20 years ago for
drive "stiction" after disuse. It seems that
worked.
On Sunday, September 19, 2021, 08:58:57 PM
PDT, Bill Degnan via
cctalk <cctalk at classiccmp.org> wrote:
I have simply opened and physically moved the disk counter clockwise a
turn, in a clean dust-free place. Or try putting in an oven on warm for
3
minutes a side, all four sides to loosen the
grease. Might sound crazy
but
these have worked for me before
Bill
On Sun, Sep 19, 2021, 10:18 PM Zane Healy via cctalk <
cctalk at
classiccmp.org>
wrote:
> 20+ years ago, I remember people talking about disassembling these to
fix
> the issue. I?ve never tried. Though I have
one or two that might
benefit
> from is. If the CLASSICCMP archives from
?97-2000 are online, I?d
> recommend running a search against them.
>
> Zane
>
>
>
>
>> On Sep 19, 2021, at 3:58 PM, Chris Zach via cctalk <
> cctalk at classiccmp.org> wrote:
>> Ok, so out of the basement came a Micrapolis 1325 (the old Dec RD53
> disk) with what appears to be stuck heads. Rotor tries to move under
power
> but can only take out slack. Will move
backwards a bit.
>> Is this stuck head, and what would be the best way to free it? The
> reason I'm asking is this disk had a SA1000 adapter mounted under it so
I
> am pretty sure it was a PERQ disk. Which
means data may be priceless.
And
of course
it's stuck.
Thoughts?
CZ
22 Sep
22 Sep
4:46 a.m.
On 9/20/21 1:13 AM, Chris Zach via cctalk wrote:
Running it through the MFM tool got all but 200 or so
sectors on the first
pass, most errors were on head 3 but tapered off after cyl 500. Seems like
a normal copy of Accent, no special information so it might not be worth
taking the world apart to get it working.
What's this "MFM tool" of which you speak? Something specific to the PERQ
world? I've got various ST506/412-type drives formatted against various
controllers in various systems that might benefit from a snapshot.
cheers
Jules
4:54 a.m.
On 22.09.21 13:46, Jules Richardson via cctalk wrote:
On 9/20/21 1:13 AM, Chris Zach via cctalk wrote:
David Gesswein's MFM-reader : https://www.pdp8online.com/mfm/mfm.shtml
Running it through the MFM tool got all but 200
or so sectors on the first pass, most errors were on head 3 but tapered off after cyl 500.
Seems like a normal copy of Accent, no special information so it might not be worth taking
the world apart to get it working.
What's this "MFM tool" of which you speak? Something specific to the PERQ
world? I've got various ST506/412-type drives formatted against various controllers in
various systems that might benefit from a snapshot.
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days inactive
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7 comments
7 participants
participants (7)
-
billdegnan＠gmail.com -
cz＠alembic.crystel.com -
healyzh＠avanthar.com -
jos.dreesen＠greenmail.ch -
jules.richardson99＠gmail.com -
kiwi_jonathan＠yahoo.com -
useddec＠gmail.com