Toshiba TV29C90 problem; Image fades to black...

[bz]

Jerry Peters <jerry@example.invalid> wrote in news:QoOOj.221484$cQ1.29403
@bgtnsc04-news.ops.worldnet.att.net:

The heads on modern HD's automatically retract when power is removed,
it's a function of the design. They do not crash into the platters.

....'should' automatically ... 'should not' crash ....

Unfortunately, design and reality diverge at times.
Also, on modern drives, the heads don't retract, they move to a 'parking
area'.
On older drives, the heads actually were removed from the area of the
platter when the drive was off.

Now, the heads never leave the platters. They actually land on the platters
when the platters stop spinning.
They take off and fly when the platters spin.

I don't know how they avoid 'sticking'.

I have seen platters with bands of magnetic coating scrapped completely off
due to head crashes.

In the late 70's, early 80's I actually replaced platters and heads and
aligned drives.

Now, the heads are so small that I can barely see them!

In any case, since win 95/98 and later systems WRITE to the hard drive
during start up, while running and during shut down, thus are updating the
directory almost constantly.
It is very likely that killing power without proper shut down will write
garbage to the directory tracks.
Once that is done, files are lost.
If you are UNLUCKY, it is your data files that get corrupted, but you don't
notice until you need them.
If you are LUCKY, the system won't boot and you must repair the op system
from the CD and repair disk you made when you installed the op system.




--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+ser@ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap

 

[Allodoxaphobia]

On Mon, 21 Apr 2008 12:02:41 +0100, Eeyore wrote:

"Michael A. Terrell" wrote:

In residential wiring Romex is very common so Black or red is all you
are likely to see

Which is line/live ? In the UK red was the live conductor for many decades (now
brown in conformity with other European countries).

In the U.S., 110VAC service, 'live' is black, and neutral is white.
Go figure.

It's always been my cynical view that this 'plan' was put in place by a
consortium of electricians to kill off do-it-yourselfers that would
assume the color coding would be rational and logical.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
*** Killfiling google posts: <http://jonz.net/ng.htm>

 

[Dave Plowman (News)]

In article <slrng0pcma.2sq9.bit-bucket@shell.config.com>,
Allodoxaphobia <bit-bucket@config.com> wrote:

In the U.S., 110VAC service, 'live' is black, and neutral is white.
Go figure.

It's always been my cynical view that this 'plan' was put in place by a
consortium of electricians to kill off do-it-yourselfers that would
assume the color coding would be rational and logical.

Trouble is a colour which is logical to one ain't to another. Ground
(earth) is usually a shade of brown - but not with electrics.

Think the unified Euro colours - green/yellow for ground, blue neutral
and brown line was arrived at to allow a colour blind person to
differentiate between them rather than any other logic.

It's one thing I'd be in favour of having a world wide standard for - and
also car wiring colours.

--
*Someday, we'll look back on this, laugh nervously and change the subject

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.

 

[Dave Plowman (News)]

In article <slrng0pcma.2sq9.bit-bucket@shell.config.com>,
Allodoxaphobia <bit-bucket@config.com> wrote:

In the U.S., 110VAC service, 'live' is black, and neutral is white.
Go figure.

It's always been my cynical view that this 'plan' was put in place by a
consortium of electricians to kill off do-it-yourselfers that would
assume the color coding would be rational and logical.

Trouble is a colour which is logical to one ain't to another. Ground
(earth) is usually a shade of brown - but not with electrics.

Think the unified Euro colours - green/yellow for ground, blue neutral
and brown line was arrived at to allow a colour blind person to
differentiate between them rather than any other logic.

It's one thing I'd be in favour of having a world wide standard for - and
also car wiring colours.

--
*Someday, we'll look back on this, laugh nervously and change the subject

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.

 

[James Sweet]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:480C7451.C7FCC976@hotmail.com...

"Michael A. Terrell" wrote:

In residential wiring Romex is very common so Black or red is all you
are likely to see

Which is line/live ? In the UK red was the live conductor for many decades
(now
brown in conformity with other European countries).

Graham

Black is live, red is also used as live, most often in a 240V circuit where
you have live on both sides. White is neutral which connects to ground in
the panel.

 

[James Sweet]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:480C7451.C7FCC976@hotmail.com...

"Michael A. Terrell" wrote:

In residential wiring Romex is very common so Black or red is all you
are likely to see

Which is line/live ? In the UK red was the live conductor for many decades
(now
brown in conformity with other European countries).

Graham

Black is live, red is also used as live, most often in a 240V circuit where
you have live on both sides. White is neutral which connects to ground in
the panel.

 

[Allodoxaphobia]

On Mon, 21 Apr 2008 17:22:29 +0100, Ian Jackson wrote:

In message Allodoxaphobia writes:
On Mon, 21 Apr 2008 12:02:41 +0100, Eeyore wrote:
"Michael A. Terrell" wrote:

In residential wiring Romex is very common so Black or red is all you
are likely to see

Which is line/live ? In the UK red was the live conductor for many
decades (now
brown in conformity with other European countries).

In the U.S., 110VAC service, 'live' is black, and neutral is white.
Go figure.

It's always been my cynical view that this 'plan' was put in place by a
consortium of electricians to kill off do-it-yourselfers that would
assume the color coding would be rational and logical.

For an Englishman, the US colo(u)r code is easy to remember.
Think 'Black Death' (http://en.wikipedia.org/wiki/Black_Death).
We used to have green for earth (ground) - but, for a long time, now
green and yellow. Close enough. Think 'England's green and pleasant
land' - 'land' = ground. The only problem is white - a sort-of 'neutral'
colo(u)r, I suppose.

Just don't get "Black = dark, cold; White = white hot" burned into your
brain.

Jonesy

 

[Allodoxaphobia]

On Mon, 21 Apr 2008 17:22:29 +0100, Ian Jackson wrote:

In message Allodoxaphobia writes:
On Mon, 21 Apr 2008 12:02:41 +0100, Eeyore wrote:
"Michael A. Terrell" wrote:

In residential wiring Romex is very common so Black or red is all you
are likely to see

Which is line/live ? In the UK red was the live conductor for many
decades (now
brown in conformity with other European countries).

In the U.S., 110VAC service, 'live' is black, and neutral is white.
Go figure.

It's always been my cynical view that this 'plan' was put in place by a
consortium of electricians to kill off do-it-yourselfers that would
assume the color coding would be rational and logical.

For an Englishman, the US colo(u)r code is easy to remember.
Think 'Black Death' (http://en.wikipedia.org/wiki/Black_Death).
We used to have green for earth (ground) - but, for a long time, now
green and yellow. Close enough. Think 'England's green and pleasant
land' - 'land' = ground. The only problem is white - a sort-of 'neutral'
colo(u)r, I suppose.

Just don't get "Black = dark, cold; White = white hot" burned into your
brain.

Jonesy

 

[GregS]

In article <1Y2Pj.7687$GE1.496@nlpi061.nbdc.sbc.com>, Bennett Price <""bjpriceNOSPAM\"@NOSPAMcal berkeley.edu"> wrote:

Thanks to all who have responded. I immediately replaced the fan with
another one - had to devise a way to mount it on the video card heat
sink which wasn't straightforward. I was just curious about why the fan
was so position sensitive.

Bennett Price > wrote:
I've got a small 12V DC .9 Watt 'muffin' fan (1.75"x1.75"x3/8").
It was the cooler for a video card's processor chip and was
frozen up.

I put a drop of oil into its sleeve bearing and it now runs
reliably - almost. It will start every time as long as it is
not oriented with the open 'face' down. (The open face is the
side in which you can see the bearing). If the open bearing is
down, it sometimes starts and sometimes needs a slight nudge to
get it going.

What's going on? How come? TIA

Sleeves slide around, ball bearing fans seem spring loaded, so position
is less important.

greg

 

[GregS]

In article <1Y2Pj.7687$GE1.496@nlpi061.nbdc.sbc.com>, Bennett Price <""bjpriceNOSPAM\"@NOSPAMcal berkeley.edu"> wrote:

Thanks to all who have responded. I immediately replaced the fan with
another one - had to devise a way to mount it on the video card heat
sink which wasn't straightforward. I was just curious about why the fan
was so position sensitive.

Bennett Price > wrote:
I've got a small 12V DC .9 Watt 'muffin' fan (1.75"x1.75"x3/8").
It was the cooler for a video card's processor chip and was
frozen up.

I put a drop of oil into its sleeve bearing and it now runs
reliably - almost. It will start every time as long as it is
not oriented with the open 'face' down. (The open face is the
side in which you can see the bearing). If the open bearing is
down, it sometimes starts and sometimes needs a slight nudge to
get it going.

What's going on? How come? TIA

Sleeves slide around, ball bearing fans seem spring loaded, so position
is less important.

greg

 

[Arfa Daily]

"rebel" <me@privacy.net> wrote in message
news:1i8p04p1gojifgtne7tt4vp97ulevnfsa4@4ax.com...

On Mon, 21 Apr 2008 13:39:45 +0100, Terry Pinnell
terrypinDELETE@THESEdial.pipex.com> wrote:

Using my Bluetooth-linked GPS unit with my iPAQ 2210 Pocket PC has the
serious downside that the 1000 mAH lithium-ion battery runs out after
3 hours or so, nowhere near long enough for a day's walking/hiking.

I'm considering buying a higher capacity battery (3300 mAH) but that
has the disadvantage that the 2210 would no longer fit its leather
case. So an alternative I'd like to explore is using conventional
(alkaline or NiMH) batteries. The lithium-ion battery is apparently
3.7V. The DC power unit plug that fits the cradle I use when at home
reads 5.28V on my meter. So a 6V set of 4 AA or C or D cells are
candidates, possibly with a diode in series. Has anyone tried this
please? I'm assuming there's protective circuitry to maintain the
appropriate voltage anyway. Presumably the lithium ion battery in
place would get charged simultaneously? Safely?

Terry, the "normal" voltage range of Lithium-Ion cells is 4v2 at full
charge
down to cutoff at typically 3v0. Oddly enough, three times what you'd
sensibly
attribute to a NiMH cell, 1v4 down to 1v0. I'd try three NiMh in a
temporary
configuration to see how it panned out.

As far as charging is concerned, any built-in charging won't match the
proper
regimes for NiMH. There are straightforward non-destructive ways to
determine
what the charger does. Altenratively, put two diodes in series with four
cells
and that way you get a better voltage match without any charging in-situ.

I think that you are mis-understanding what Terry is asking. I think that
what he is saying is that he would like to have a sort of 'battery belt'
arrangement fabricated from dry cells or NiMH or whatever, totalling 6v, to
effectively form a long duration 'field replacement' for the home-based
mains power charger, and plugging into the GPS via the same plug as the home
charger. If that is indeed what he is asking, then there should be no
problem with this. It's basically the pedestrian equivalent of running it in
the car, via a 12v car adapter, which I'm sure is probably available. In
fact, this might be another possibility. Look to see if a car adapter is
available (there's a good place in the UK called
globalpositioningsystems.co.uk) and if so, you could hook it to a small 12v
gel battery, that would be no heavier to carry around than a bunch of dry
cells. That way, your GPS will be powered, and the internal battery will
remain 'topped up'. I do a similar thing when I take my GPS out in the
wife's car, the cradle being normally in my car.

Arfa

 

[GregS]

In article <82ada154-f5aa-4b21-aa91-7e72fbc9a85a@d45g2000hsc.googlegroups.com>, Joe <joe5345@gmail.com> wrote:

I have no cell service in my basement but I'd like to be able to take
a call without running up the stairs. Could I splice a 50ft extension
cord into my headset? I figure there are two wires inside for for
talking and the other for listening so it should work, no?

I don't know if its possible, but if you live in a decent area, you might also try a
passive repeater.

If your handy and you live in a good signal area, which I doubt, attach two cell phone
antennas with a 50 foot piece of coax. i don't know if it would work.


There is also fancy stuff available. some commercially oriented or this consumer
item............
http://www.phonelabs.com/prd05.asp

 

[ian field]

"Robert LaCasse" <scooter@yamaha.info> wrote in message
news:uqdg04d94lfo88d0gidophu8p74frhr0f4@4ax.com...

On Thu, 17 Apr 2008 22:13:13 -0700, Dennis Lee Bieber
wlfraed@ix.netcom.com> wrote:

|>> I tested some battery chargers last night , and found "as usual"
|>> that the amps and voltages stated on the modules were not the same as
what I
|>> found on the Volt and Amp testers....
|
|> HOW did you test? Just hooking a DVM across the leads will not give
|>reasonable readings.
|
Right, that's my problem with some of my chargers, since "you can't
believe everything you read on the chargers" that was the best way of
checking the "real" volts/amps, but applying a known amp load might
help....

Most basic chargers have only rectification of the secondary voltage not
smoothing, so the reading with a DMM is likely to be very inaccurate. If you
put an electrolytic capacitor on the output it will charge to the peak
voltage (1.414 x RMS) but as others have stated battery charger transformers
are impedance regulated - that is they have a higher than stated voltage off
load which drops to around 13.8 - 14.4V on load, transformers for general
purpose power supplies (including wall warts) are definitely not suitable
for Pb battery charging unless they have electronic current limiting (like
the LM317 as others have suggested) and then the secondary voltage must be
higher by at least the minimum drop out voltage of the current limit chip.

 

[ian field]

"Robert LaCasse" <scooter@yamaha.info> wrote in message
news:uqdg04d94lfo88d0gidophu8p74frhr0f4@4ax.com...

On Thu, 17 Apr 2008 22:13:13 -0700, Dennis Lee Bieber
wlfraed@ix.netcom.com> wrote:

|>> I tested some battery chargers last night , and found "as usual"
|>> that the amps and voltages stated on the modules were not the same as
what I
|>> found on the Volt and Amp testers....
|
|> HOW did you test? Just hooking a DVM across the leads will not give
|>reasonable readings.
|
Right, that's my problem with some of my chargers, since "you can't
believe everything you read on the chargers" that was the best way of
checking the "real" volts/amps, but applying a known amp load might
help....

Most basic chargers have only rectification of the secondary voltage not
smoothing, so the reading with a DMM is likely to be very inaccurate. If you
put an electrolytic capacitor on the output it will charge to the peak
voltage (1.414 x RMS) but as others have stated battery charger transformers
are impedance regulated - that is they have a higher than stated voltage off
load which drops to around 13.8 - 14.4V on load, transformers for general
purpose power supplies (including wall warts) are definitely not suitable
for Pb battery charging unless they have electronic current limiting (like
the LM317 as others have suggested) and then the secondary voltage must be
higher by at least the minimum drop out voltage of the current limit chip.

 

[Allodoxaphobia]

In article <82ada154-f5aa-4b21-aa91-7e72fbc9a85a@d45g2000hsc.googlegroups.com>, Joe <joe5345@gmail.com> wrote:
I have no cell service in my basement but I'd like to be able to take
a call without running up the stairs. Could I splice a 50ft extension
cord into my headset? I figure there are two wires inside for for
talking and the other for listening so it should work, no?

And, how were you planning on answering the call?
And, does your cell phone ring through the speaker , or through a
seperate sounder/speaker?

 

[Allodoxaphobia]

In article <82ada154-f5aa-4b21-aa91-7e72fbc9a85a@d45g2000hsc.googlegroups.com>, Joe <joe5345@gmail.com> wrote:
I have no cell service in my basement but I'd like to be able to take
a call without running up the stairs. Could I splice a 50ft extension
cord into my headset? I figure there are two wires inside for for
talking and the other for listening so it should work, no?

And, how were you planning on answering the call?
And, does your cell phone ring through the speaker , or through a
seperate sounder/speaker?

 

[Jerry Peters]

Jeff, WB8NHV <jeffhs@ameritech.net> wrote:

On Apr 20, 6:16 pm, Jerry Peters <je...@example.invalid> wrote:
Jeff, WB8NHV <jef...@ameritech.net> wrote:
On Apr 17, 8:51 pm, cuhu...@webtv.net wrote:
Your DVD drive could be defective.So could that second power drive
tone of the worst things to do with a computer is to physically
unplug that computer without properly shutting the computer down first.
cuhulin

I agree. Shutting a computer down by simply unplugging it (a method
I call "brute force") rather than using the correct shutdown procedure
can and often does corrupt the operating system, requiring that the
entire OS be reinstalled--not to mention all your application programs
you may have installed at the time. Most of the time the computer will
go into safe mode if it is shut down other than by the recommended
procedure, but I wouldn't count on it. I don't even remember how many
times my first Windows computer (running Win95) crashed and corrupted
the operating system when I tried to shut down the system with the
brute force technique. (I don't do that anymore with my current
Win98SE system unless I have to, say if the computer freezes and
absolutely cannot be shut down normally; live and learn.) Another
problem with shutting down simply by pulling the plug is that the hard
drive may have errors on it when the system is restarted; many if not
most Windows computers are set up by default to scan the hard disk as
soon as the system boots after a crash. The system can be set to
repair automatically any errors thus found.

Still another potentially fatal (for the computer) problem created by
the act of shutting down without following the correct procedure is
that the read/write heads of the hard disk will literally crash into
the disk, again with the potential for disk errors when the system
is rebooted. These crashes will eventually ruin your hard drive, so it
is best to avoid them if possible. Occasional disk crashes are
inevitable (power outages, for example), but here I am speaking of
unnecessary hard disk crashes caused by incorrect shutdowns; for
maximum trouble-free life of your hard disk, please, for gosh sakes
use the Windows-recommended shutdown method. This can be accessed
directly from the Start menu by clicking on "Shut Down" and selecting
the option of the same name from the menu which appears, or by doing
the so-called "three-finger salute", i.e. pressing Ctrl+Alt+Delete
while the computer is powered up.

The heads on modern HD's automatically retract when power is removed,
it's a function of the design. They do not crash into the platters.

Jerry



Jeff Strieble, WB8NHV
Fairport Harbor, Ohio USA

That may be true for today's hard drives (used in new laptops and
desktop systems), but I was referring to the hard drive in my IBM
Aptiva 595 system which was new eight years ago. Were the read/write
heads on HDs of that vintage designed to retract on power down as
well? If so, I'm sure I was worrying for nothing every time the disk
crashed on that system and my first Windows computer circa 1997 (AST
Adventure! model 200).

My first computer, bought in 1989, came with a 79MB IDE HD with a
voice-coil actuator. It's an intrinsic part of the VC design that the
heads retract when power disappears.

The old "head parking required" drives used a stepper motor actuator;
when the power went down, the heads would be left wherever they were
last positioned.

Jerry

 

[Jerry Peters]

Jeff, WB8NHV <jeffhs@ameritech.net> wrote:

On Apr 20, 6:16 pm, Jerry Peters <je...@example.invalid> wrote:
Jeff, WB8NHV <jef...@ameritech.net> wrote:
On Apr 17, 8:51 pm, cuhu...@webtv.net wrote:
Your DVD drive could be defective.So could that second power drive
tone of the worst things to do with a computer is to physically
unplug that computer without properly shutting the computer down first.
cuhulin

I agree. Shutting a computer down by simply unplugging it (a method
I call "brute force") rather than using the correct shutdown procedure
can and often does corrupt the operating system, requiring that the
entire OS be reinstalled--not to mention all your application programs
you may have installed at the time. Most of the time the computer will
go into safe mode if it is shut down other than by the recommended
procedure, but I wouldn't count on it. I don't even remember how many
times my first Windows computer (running Win95) crashed and corrupted
the operating system when I tried to shut down the system with the
brute force technique. (I don't do that anymore with my current
Win98SE system unless I have to, say if the computer freezes and
absolutely cannot be shut down normally; live and learn.) Another
problem with shutting down simply by pulling the plug is that the hard
drive may have errors on it when the system is restarted; many if not
most Windows computers are set up by default to scan the hard disk as
soon as the system boots after a crash. The system can be set to
repair automatically any errors thus found.

Still another potentially fatal (for the computer) problem created by
the act of shutting down without following the correct procedure is
that the read/write heads of the hard disk will literally crash into
the disk, again with the potential for disk errors when the system
is rebooted. These crashes will eventually ruin your hard drive, so it
is best to avoid them if possible. Occasional disk crashes are
inevitable (power outages, for example), but here I am speaking of
unnecessary hard disk crashes caused by incorrect shutdowns; for
maximum trouble-free life of your hard disk, please, for gosh sakes
use the Windows-recommended shutdown method. This can be accessed
directly from the Start menu by clicking on "Shut Down" and selecting
the option of the same name from the menu which appears, or by doing
the so-called "three-finger salute", i.e. pressing Ctrl+Alt+Delete
while the computer is powered up.

The heads on modern HD's automatically retract when power is removed,
it's a function of the design. They do not crash into the platters.

Jerry



Jeff Strieble, WB8NHV
Fairport Harbor, Ohio USA

That may be true for today's hard drives (used in new laptops and
desktop systems), but I was referring to the hard drive in my IBM
Aptiva 595 system which was new eight years ago. Were the read/write
heads on HDs of that vintage designed to retract on power down as
well? If so, I'm sure I was worrying for nothing every time the disk
crashed on that system and my first Windows computer circa 1997 (AST
Adventure! model 200).

My first computer, bought in 1989, came with a 79MB IDE HD with a
voice-coil actuator. It's an intrinsic part of the VC design that the
heads retract when power disappears.

The old "head parking required" drives used a stepper motor actuator;
when the power went down, the heads would be left wherever they were
last positioned.

Jerry

 

[Jerry Peters]

bz <bz+ser@ch100-5.chem.lsu.edu> wrote:

Jerry Peters <jerry@example.invalid> wrote in news:QoOOj.221484$cQ1.29403
@bgtnsc04-news.ops.worldnet.att.net:

The heads on modern HD's automatically retract when power is removed,
it's a function of the design. They do not crash into the platters.

...'should' automatically ... 'should not' crash ....

Unfortunately, design and reality diverge at times.
Also, on modern drives, the heads don't retract, they move to a 'parking
area'.
On older drives, the heads actually were removed from the area of the
platter when the drive was off.

Now, the heads never leave the platters. They actually land on the platters
when the platters stop spinning.
They take off and fly when the platters spin.

I don't know how they avoid 'sticking'.

I have seen platters with bands of magnetic coating scrapped completely off
due to head crashes.

When I worked for a large aluminum company, I had a 14" platter from a
crashed drive, the aluminum substrate had been gouged by the heads in
at least a 1/2" wide circle.

In the late 70's, early 80's I actually replaced platters and heads and
aligned drives.

Again at the large Al company we had some IBM 3380 drives where the
head actuators retracted against a rubber bumper. Over time the rubber
degraded and became sticky, the IBM CE's actually replaced or covered
the rubber bumpers with new ones, while the disk were spinning! Turns
out that the disk assemblies while having a clear plastic surround,
were not really sealed.

Now, the heads are so small that I can barely see them!

In any case, since win 95/98 and later systems WRITE to the hard drive
during start up, while running and during shut down, thus are updating the
directory almost constantly.
It is very likely that killing power without proper shut down will write
garbage to the directory tracks.
Once that is done, files are lost.
If you are UNLUCKY, it is your data files that get corrupted, but you don't
notice until you need them.
If you are LUCKY, the system won't boot and you must repair the op system
from the CD and repair disk you made when you installed the op system.

Not in my experience. Given the number of times W9x locked up with no
alternative but to do a hard reset, I have had few problems. Never had
to do a reinstall because of this.
Depending on how and what NTFS journals, XP should be good in that
regard also.

Jerry

 

[Jerry Peters]

bz <bz+ser@ch100-5.chem.lsu.edu> wrote:

Jerry Peters <jerry@example.invalid> wrote in news:QoOOj.221484$cQ1.29403
@bgtnsc04-news.ops.worldnet.att.net:

The heads on modern HD's automatically retract when power is removed,
it's a function of the design. They do not crash into the platters.

...'should' automatically ... 'should not' crash ....

Unfortunately, design and reality diverge at times.
Also, on modern drives, the heads don't retract, they move to a 'parking
area'.
On older drives, the heads actually were removed from the area of the
platter when the drive was off.

Now, the heads never leave the platters. They actually land on the platters
when the platters stop spinning.
They take off and fly when the platters spin.

I don't know how they avoid 'sticking'.

I have seen platters with bands of magnetic coating scrapped completely off
due to head crashes.

When I worked for a large aluminum company, I had a 14" platter from a
crashed drive, the aluminum substrate had been gouged by the heads in
at least a 1/2" wide circle.

In the late 70's, early 80's I actually replaced platters and heads and
aligned drives.

Again at the large Al company we had some IBM 3380 drives where the
head actuators retracted against a rubber bumper. Over time the rubber
degraded and became sticky, the IBM CE's actually replaced or covered
the rubber bumpers with new ones, while the disk were spinning! Turns
out that the disk assemblies while having a clear plastic surround,
were not really sealed.

Now, the heads are so small that I can barely see them!

In any case, since win 95/98 and later systems WRITE to the hard drive
during start up, while running and during shut down, thus are updating the
directory almost constantly.
It is very likely that killing power without proper shut down will write
garbage to the directory tracks.
Once that is done, files are lost.
If you are UNLUCKY, it is your data files that get corrupted, but you don't
notice until you need them.
If you are LUCKY, the system won't boot and you must repair the op system
from the CD and repair disk you made when you installed the op system.

Not in my experience. Given the number of times W9x locked up with no
alternative but to do a hard reset, I have had few problems. Never had
to do a reinstall because of this.
Depending on how and what NTFS journals, XP should be good in that
regard also.

Jerry