Busting CRTs (was Re: Gold price was: Re: ebay feedback)

From: John B <dylanb_at_sympatico.ca>
Date: Tue Dec 7 16:23:03 1999

-----Original Message-----
From: jpero_at_cgocable.net <jpero_at_cgocable.net>
To: Discussion re-collecting of classic computers
Date: Tuesday, December 07, 1999 6:02 PM
Subject: Re: Busting CRTs (was Re: Gold price was: Re: ebay feedback)

> >--- John B <dylanb_at_sympatico.ca> wrote:
> >
> >> >I just did that accidentally to a Mac SE. :-( I was trying to remove
> >> >cable from the innards and my hand slipped and wacked the board on the
> >> >back of the CRT and skewed it far enough to bust that little tit.

> >That was me. I heard this unmistakable noise and just sat there, a
> >of my own carelessness.

Me too! Except that is generic mono monitor. The chassis was too
flexiable and it tipped down, slewing that CRT board. Snap+hiss!
Replaced it at my expenese out of my only working monitor. :-O

> >
> >> The SEs also had those bad hard drives... the Principal
> >> Secretary actually had a large screw driver next to his SE... Every
> the
> >> drive wouldn't spin up he would beat the crap out of it. Apple came
> and
> >> they agreed to replace all the flaky hard drives free immediately.
> >
> >I still have a Quantum PD1800S that has stiction. I paid $1100 for it
> >and they didn't consider it to be a warrantable problem. I'll never buy
> from
> >them again.
> >

The primary cause is bad cooling for those hot running HDs, I'm not
putting the Quantum in with that offenders for that problems, it
wasn't the bearing, it was grabby platters. True cause are too many
spin ups and shutdowns, letting it run too hot caused the grabby
platters. Grabby platters happens because the lube ran out from
center by flinging action when real hot. Heads happens to park at
inner cylinders and you'll know what happens...

> This brings back really funny memories. Every so often I'd get called out
> come up to their Mac and punch it really hard. [you *had* to see their
> faces.]. Then. hear the drive spin up and walk away.

That punching that thing is what jarred free those grabby platters.
That is only treating the symtoms. The true fix is new HD and
new 3.9uF 250V NP cap & yoke male connector, resolder the
trouble spots. Use screensaver always. Customers pays the backup
job and teach them to do it regliously.
Yes and that is what Quantum did. We always used screen savers (home brewed
for security), and getting users to backup or even server based backups are
headaches... Most people don't like to do it.. most forget to leave their
computer off.. we sent them warnings and they did not care until they lost

> Those quantum drives were awful. As back up policies were rarely adhered
> it was my job to pull the drives apart and get the data out at any

It wasn't the quantum's problems. I see Conners and few others that
were being cooking inside those hot boxens without good cooling go
bad. The best solution is cooler running HDs for those boxens that
do have poor cooling design.
No other drive (and we had every mac and every possible drive including):
IBM i think
had this problem BUT quantum. In fact, we never had a sticky platter in 10
years across a few thousand computers except for quantum.

> (were talking replacing the motor). A rep and engineer from quantum came
> to see what I was doing.... They weren't going to replace the new drive
> I had cannibalized until they were told we had enough of their broken
> garbage..

Wow. HOW on earth that is possible!? the motor spindle casing is
pressed into spindle axle. That casing has to go in order to get at
coil assembly. Yes I played with those dead quantum 40S, 80S and any
105S HH 3.5" ones that used both optical + sectors feedback
tracking. These dead ones died bec of grabby platters getting too
great to overcome and platters starts to lose data bits and the
bearings were still good and like new. Those ones that overheated
platters looks defect-free, no 4-pits and no crash trackings but
difference is it lost the surface lube/finish.

If I could not spin the platter by hand I would remove the platters and put
them in a new drive. We have a clean room for that purpose. It got
impossible on the larger, newer drives. There is a data recovery shop in
North Bay that does this kind of work too.

After getting the drive spun up I would use a SCSI util to make an image
copy of what it could to a new drive. Sometimes when the data was really
badly beaten or the dir was toasted I wrote some apps that would seek out
known headers and copy huge blocks and try and put the data back together.
Our communications server went down once and we lost all of our PageMaker
files. The drive had destroyed most of the directory entries.... so I was
pulling off huge chunks of pagemaker files and putting them back together.

Other projects of interest I had to do back in the early '90s were :

Screen Saver & Shredder (write 3 times over data put in trash) - If I
remember correctly I patched the "DrawMenuBar".. this handled the screen
saver [security]. The shredder of course wiped out all file data 3X when
trash was emptied.

Patch System File - RESOURCE was ZSYS or SYSZ?? (It's been a while..1992)...
all assembly language.. This program had to be able to attach itself to
other computers on other nets and report back by talking to a major public
domain server. It checked the server for "remote commands" inside a
hypercard file and executed them. It was 2.4K (68000). It also had to get
around Sam Intercept... that was pretty easy. This will probably be in a
book in 2004 when I can talk about it in detail.

many other projects but too recent to list yet.

Even fabled Barracudas die from heat.  I recently aquired one that is
still good  (ST12550N) and experimented on it.  Heated up like mad
without airflow.  Still will heat up even case w/ hd inside with some
airflow.  Noted that and knew this by reputation and I put a muffin
fan at front end blowing on the "steel cage" and allowing free air
rush across the top circuit.  Cool temp as it should be with this
simple fan solution.
> I still have a Quantum PD1800S that has stiction.  I paid $1100 for
> it new and they didn't consider it to be a warrantable problem.
> I'll never buy from them again.
> -ethan
Ethan, my curious:  that HD, did it run hot or bit too much warm?
That is the primary problem.  PD1800S is old design and runs hot.
Did that HD sit all cooped up behind bezel or internally?
My HDs now are mounted in new ways with bigger open or 3.5" bezel
left off and they run at room temp or less.  INCLUDING that "new" WD
9.1GB expert 7200rpm.   The old LPS 540 is still living daily serving
as data archival along with bit more warmer fireball EX.  CR, CX and
any fireballs run bit more warm or hot when cooling is poor.
I have lost 4 Micropolis 4345WS drives over the past couple of years due to
heat. I gave up on standard mouting and just stuffed an old mini fan  right
above it.
> john
Received on Tue Dec 07 1999 - 16:23:03 GMT

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