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EvilBob
2005-Jul-11, 12:47 AM
I'm hoping someone here has expertise in this area who can help! Forgive me if the explanation here is a bit long...

We have a client who is in a motorised wheelchair. For years she has had problems losing data on her floppy disks - I've taught her to use a hard plastic case to put her disks into, not to eject the disk until the drive light has gone out, and (thankfully) also taught her the importance of backing-up, and the impermanence of floppy disks as a storage medium. But we've never really solved the problem.
This morning, one of the staff here has suggested that the magnetic fields from the motor in her wheelchair might be the cause.
#-o
Now why didn't I think of that? She has a bag slung over the back of her chair, hanging right down to the level of the motor under the seat. Any disk dropped in the top will find its way to the bottom.

My first question is - Could this be the case? I don't know how powerful the fields generated by a motor of this type are, or how strong a field a disk will cope with before data is lost.
And secondly, is there any way of shielding the disks to stop it? Would a metal disk box of some type protect the disks, or is the only answer to keep the disks somewhere else?

Anybody have any ideas? I did think of making her a tin-foil hat ....

Maksutov
2005-Jul-11, 01:04 AM
Yes, it could be the case. Some electric motors have large permanent magnets, others without PMs still generate magnetic fields.

Best thing to do would be to make a copy of a disk, and subject it to worst-case conditions re proximity to the motor. Time and use of the wheelchair would have to be factored in.

If the disk remains readable, then the problem is elsewhere. If not, either advise her to carry the disks somewhere else, keep the bag with the disk in it somewhere else, or get a shielded container.

Better yet, install a DVD RW drive, and use RW disks. These are impervious to magnetic influences.


[edit/typo]

Metricyard
2005-Jul-11, 01:39 AM
It's quite possible that the floppies are being damaged by the magnets.

I wouldn't rule out the floppies themselves though. They're pretty cheap these days,(and I mean cheap as in poor quality). I've opened many boxes in the last few years and seen a major DOA rate to them, and a poor shelf life for those that do work.

Might be time to upgrade to a USB thumb disk. Much greater storage and a bit more reliable.

Enzp
2005-Jul-11, 02:24 AM
Isolate the problem. it is the motors or not, it is magnetic fields or not, it is the floppies themselves or not, it is something about the storage or not, it is the floppy drive itself or not.

If discs never carried about are OK, then the drive is likely OK too.

Try using high quality floppies in the same exact ways. If it makes a difference, it is a factor. Otherwise it is not.

A metal box of thin steel - like a little file card box or "recipe" box - should keep out the evil magnetism.

Get a little hand compass from a boy scout and hold it where the floppies usually store in the motor area. See if the motor fields deflect it. Try this both sitting and running. It might not be the magnet per se, The motor currents can generate strong fields on their own. This would only show up while the motors are energized and running.

And do Mak's test with a test-purpose disc.

Gullible Jones
2005-Jul-11, 02:36 AM
I have seen good floppies go bad after being written to; I have seen them go bad after being read; I have seen them become corrupted beyond all repair just by sitting on my desk unused for a few days. Floppies are hideously unreliable media; I would not be at all surprised if exposure to the magnetic fields generated by a wheelchair motor caused irreparable damage in almost every case.

hippietrekx
2005-Jul-11, 04:19 AM
I took back-up floppies with all of my data, reports, charts, and backboard information with me to the Intel International Science and Engineering Fair. I carried my hard copy report with me, but I needed the backboard info on the disks just incase my science project didn't get shipped properly and I needed to make repairs or a new backboard (the fair was about 700 miles away, so taking my PC on the plane or going home wasn't an option.)

Anyway, these were the top-of-the-line disks. I even double-checked them on my computer to see if the data was there. When I went through airport security, I removed my disks before I got to the metal detector, like I'm supposed to, and handed them to the airport security guard. I told him the disks needed to be hand-checked. I watched him put them in a box, and the box was passed around the metal detector over 4 feet from it, to the end of the line and put in the bin with my shoes and belt. I walked through the detector and retrieved my items. When I got to the hotel and used another contestant's laptop to see if the info was there, the disks were empty and said "Error: Files not found"

Luckily my project was safe and sound in my official area at the fair with not problems and in one piece. Yay! I suspect that the disks were affected my the metal detector, but from now on, I'm burning RWs, just in case. If my project had been damaged, I would have really been in deep water!

--htx

Chuck
2005-Jul-11, 04:50 AM
I haven't had good results with RW CDs holding their data for very long. The write once CDs are better but you need a new one each time you make backups. Fortunately they're really cheap now. Another advantage is that any ordinary CD drive can read them.

I have a 2 GB AIM.COM mailbox and a 2+ GB Gmail mailbox to which I email zipped copies of important files. I can download them from anywhere.

Maksutov
2005-Jul-11, 05:42 AM
I haven't had good results with RW CDs holding their data for very long. The write once CDs are better but you need a new one each time you make backups. Fortunately they're really cheap now. Another advantage is that any ordinary CD drive can read them.

I have a 2 GB AIM.COM mailbox and a 2+ GB Gmail mailbox to which I email zipped copies of important files. I can download them from anywhere.
I have a number Ricoh CD-RWs from 1999 with six year old data on them and they work just fine. Maybe you got a bad production run, or semi-compatible CD-RWs?

On the other hand if you time your buying just right, CD-Rs may be had for $0.00 each nowadays.

On-line storage is convenient in may ways, but is also subject to

1. The service provider staying in business
2. The particular part of the RAID where your data is not getting corrupted
3. The site not getting hacked.

That's one of the many real advantages to removable storage. Once out of the computer it can't be reached by a hacker through the network.

Meanwhile the DVD RWs I was referring to are showing no signs of data loss. These are stored in cool, dry, dark places, which is an environment recommended for all types of media, even books. :wink:

zebo-the-fat
2005-Jul-11, 09:43 AM
What's a floppy? :D

I use a USB pen drive, small (hangs on my keyring), lots of storage, no moving parts works with almost any PC with a USB socket ... it's the best thing I ever bought.

Bilateralrope
2005-Jul-11, 09:59 AM
What's a floppy? :D

I use a USB pen drive, small (hangs on my keyring), lots of storage, no moving parts works with almost any PC with a USB socket ... it's the best thing I ever bought.

And they are unaffected by magnets.

In about march I added some hardware to my computer. In doing this I had to unplug the data cable from the floppy drive, then plug it back in. Since then my floppy drive hasn't worked. I suspect that I plugged the data cable in the wrong way (some cables have a bump on the connectors to prevent this, some don't. First time I encountered an IDE cable that could be lugged in the wrong way, I did and couldn't work out what I did wrong), but I don't have any need for it, so I haven't got round to checking it.

Conclusion: USB pen drives have supassed floppy disks in all aspects to the point that some computers don't even come with floppy drives as standard anymore.

Laguna
2005-Jul-11, 10:08 AM
What's a floppy? :D

I use a USB pen drive, small (hangs on my keyring), lots of storage, no moving parts works with almost any PC with a USB socket ... it's the best thing I ever bought.
And they even survive some rounds in your washing machine.
At least my USB pen did. :D

Edited for spelling

zebo-the-fat
2005-Jul-11, 10:17 AM
And they even survive some rounds in your washing machine.
At least my USB pen did.

Nice! I bought a cheap "no-name" pen drive, it worked fine for about 6 months then it died. The PC told me it had "found a new device" but couldn't work out what it was! I replaced it with a Corsair drive, this works fine, is faster and has a lifetime guarantee, (I think that means if the pen drive fails they send a hit squad round to end your lifetime! :o )
So get a well known make and you will never use a floppy again!

Some PC's can even boot from a pen drive, but it depends on the bios)

Maksutov
2005-Jul-11, 10:32 AM
Sorry to interrupt the pen drive love fest, but...

For example, about the lowest price out there for a 1GB pen drive is $65.00. Hell, I can store that much on a DVD±RW and still have 3.7GB left over. And that's for about $2 (or less when on sale) per DVD±RW disk, which works out to about $0.54 US for 1GB. With the $64.46 left over one can buy a decent DVD burner that will do a lot more than a pen drive, and whose cost will amortize as it's used.

Let's see, $65.00 versus $0.54 for 1GB of storage. Which shall I choose? :-k

zebo-the-fat
2005-Jul-11, 01:29 PM
You can't hang it from your keyring! (not and put it in your pocket that is!) :D

Laguna
2005-Jul-11, 01:38 PM
And you can use your RW only on computers with a DVD/RW Drive.
My USB pen works on every computer with USB.
Easy and fast from the explorer.

Maksutov
2005-Jul-11, 02:16 PM
And you can use your RW only on computers with a DVD/RW Drive.
My USB pen works on every computer with USB.
Easy and fast from the explorer.
Ah, but with a DVD or CD burner one can create a CD-RW with 70% of the capacity of a $65 pen, but with a cost per disc of about $0.50 or less. So, let's see, that's $0.71 for the same storage as a $65.00 pen.

But then, there are so few computers out there with CD-ROM drives that it's a real handicap.

:D

PS: There are computers currently being manufactured and sold that don't have DVD drives? How is it that these manufacturers are getting away with selling obsolete equipment?

Nethius
2005-Jul-11, 03:31 PM
Like others here, I have had very bad luck using floppies... even writing to, or reading from, can cause them to go bad.

CD burners go for $30 buck and up (Canadian) and DVD burners from $70 and up. Media very cheap.

Maybe it's time for an upgrade?

Maksutov
2005-Jul-11, 03:50 PM
Like others here, I have had very bad luck using floppies... even writing to, or reading from, can cause them to go bad.

CD burners go for $30 buck and up (Canadian) and DVD burners from $70 and up. Media very cheap.

Maybe it's time for an upgrade?
It's time.

Shop around. I got my DVD burner from Newegg for $52 (US). It's been working for a couple of years now without a glitch.

Rooting4Oppy
2005-Jul-11, 05:49 PM
People still use floppy disks? :o

I haven't used a floppy disk in, must be 6 years now. I bought an iMac when they first came out which didn't have a floppy drive. Each mac I've purchased since then (I'm on my 3rd, a G4 powerbook which is only 3 months old) hasn't had a floppy drive.

It's one of these : http://www.apple.com/powerbook/ (the 15" one).

I carry a lot of files around on my iPod which gives me loads of space, but I also have a small thumb drive for quick and easy access. I use them when I don't have my powerbook with me of course.

For backing up large amounts of data or permenant storage, I just burn a DVD with the powerbook which has a drive which can write DVD's as well as CD's.

I would really, really hate to go back to using a floppy disk after all these years. They're so small! 1.4Mb of data. Thats pretty much useless for me.

The Supreme Canuck
2005-Jul-11, 05:56 PM
Kind of a related question: have they resolved the compatibility issues with different DVD RW formats yet? I suspect yes, but I'm curious.

Nethius
2005-Jul-11, 06:29 PM
People still use floppy disks?

You would think the days of the old floppies would be gone, but alas, you still need them on certain occasions. Speaking strickly on a PC (not Mac)...

Mainly used before any OS installed.

Need them to Format a Hard Drive or partition one (but you can do this during a windows install)

To upgrade you system Bios. Some will allow through Windows, but most require you to boot with a floppy.

Also when installing Windows and you need to install 3rd party drivers, a floppy is required.

I've ran into the last 2 recently!

Lance
2005-Jul-11, 09:39 PM
Kind of a related question: have they resolved the compatibility issues with different DVD RW formats yet? I suspect yes, but I'm curious.

Yeah, by making all the drives multi-format. Most drives now are DVD ±R ±RW. Hey, it works...

TrAI
2005-Jul-11, 11:24 PM
I have a feeling that many floppies these days are of rather poor quality, I think it may be because of lower market viability, so that manufacturers must either increase prices or lower the quality. Most use of floppies these days are one shot things anyway, to move some small files from one place to another. It is quite possible for them to be messed up by the powerful magnetic fields from high current motors(though the likelihood for some data to be lost to magnetic fields is probably dependant on how important the data is, if it is very important, its likely to be lost, if it is not interesting at all its likely to remain good, and if it is of vital importance that the data is erased(for example the law is kicking in the front door and you are trying to get rid of incriminating stuff) the data is likely to remain viable beyond fimbulvinter ;-p).

Actually I would say that USB memory devices are rather good things for moving data between two places. I have found that many computers that many people use, like in schools and libraries does not have the needed stuff to write a CD, but many places do have platforms new enough to support USB mass storage devices.

As for price, well, a quick look at some web shop I found out that Floppies are about twice the price per MB to that of a USB flash device, and CD RW are about twice the price of flash devices for the number of write cycles(good modern flash devices have 100k write cycles and special hardware to distribute the usage over the entire medium to reduce wear of a specific location, while CD RWs can only do 1000 cycles it seems, so you are likely to use 100 CDs in the same space of time.) This comparison is of course dependant on the user having the same usage pattern for all the media.

So, I would conclude that Floppies are useful mostly for small stuff, but are slow and unreliable these days, USB flash devices are good for moving around data, they are compact, quick and most newer systems are likely to support them, they are however more expensive per MB than CDs and due to the ease of use one may come up against the lifetime limitation quicker than one realizes. CDs/DVDs are good for temporary storing massive amounts of data, so between machines that you can use these they are quite viable. CD-Rs are usefull some times too... Choose good CDs though, cheap CDs are notoriously unreliable, its rather annoying having the CD you burned your backups on fail.

Of course, there is another option, an USB hard drive, they have plenty of space, can be used on the same machines as USB flash devices, they have good life expectancy if not abused and are simple to use and fast. They are however more sensitive to shock and abuse than flash devices, and are likely to need an external power source(though the one using disks for portable devices are likely to be able to be powered by an USB port, but HDDs for these are a bit more expensive)

EvilBob
2005-Jul-12, 12:29 AM
I should have known this would turn into a media types/Mac/Windows debate!
Thanks for the input, guys. I'm trying Mak's suggestion of identical disks, one near the motor and one control, to make sure that it is the problem, although I'm sure that it is. I've also taught her how to burn to a CD-R (we didn't have any RWs, and our PCs here don't have DVD burners.
The pen drive is a good idea, apart from cost. But this student has a rather old PC at home which runs on Win98. This would probably be ok, except that the USB ports are all at the back of the machine, which makes it a little inconvenient for someone with Cerebral Palsy, which is the reason she has the wheelchair. Cost also means she can't afford to upgrade.
The only other suggestion I have had, apart from 'Get up and walk' (she laughed at that, I'm glad to say. I wouldn't have said it myself!) was to put her disks in a metal box, which would make a Faraday cage around them. Would we need a particular metal for this, or any other considerations?

GDwarf
2005-Jul-12, 01:07 AM
USB 'thumb' drives are great. I currently use a 128MB one, sure it cost a fair amount $30 or so CND, but it can be used more often then a CD/DVD RW, is more portable then a CD/DVD And works on any computer from Win. 98 SE.
It also takes far less time to transfer Data to it then a CD RW.
I actually bought mine because I'm doing a computer course in school (Well, was doing, summer vacation and all that). Normally that would be fine, but the school has a strict no e-mail policy (For understandable secruity reasons, although I find it funny that they keep talking about secruity yet have Windows XP (No service packs) and the only available browser is IE, also, their anti-virus software is out of date, and they don't scan for spyware. Yet apparently it's obviously a student's fault should something on the PC stop working ](*,)) and most of the computers that do have CD drives don't recognise that they exist. Floppies just can't store the amount of Data I need, and CDs/DVDs/e-mail aren't viable alternatives, so I decided on a USB drive.
As for USB ports being in the back of the PC, I have that problem as well, you should be able to find a USB extender cable for about $7 CND somewhere in your area. Then you just plug it into the slots in the back and bring it around to the front. (Don't be fooled by Best buy etc. offering you USB extender cable for $20+, I have a good reliable one that cost next to nothing.)

TrAI
2005-Jul-12, 01:16 AM
I should have known this would turn into a media types/Mac/Windows debate!
Thanks for the input, guys. I'm trying Mak's suggestion of identical disks, one near the motor and one control, to make sure that it is the problem, although I'm sure that it is. I've also taught her how to burn to a CD-R (we didn't have any RWs, and our PCs here don't have DVD burners.
The pen drive is a good idea, apart from cost. But this student has a rather old PC at home which runs on Win98. This would probably be ok, except that the USB ports are all at the back of the machine, which makes it a little inconvenient for someone with Cerebral Palsy, which is the reason she has the wheelchair. Cost also means she can't afford to upgrade.
The only other suggestion I have had, apart from 'Get up and walk' (she laughed at that, I'm glad to say. I wouldn't have said it myself!) was to put her disks in a metal box, which would make a Faraday cage around them. Would we need a particular metal for this, or any other considerations?

Well, the problem with the USB ports being on the back of the machine can be solved by connecting an USB hub or even just a cable for extending USB cables. She is likely to need at least Win98 SE, an USB v1.1 port and a driver for the USB memory device(the manufacturer have them for download). Newer versions of windows have built in support for these devices.

Magnetic fields are rather hard to shield against, though you could try a container of iron/steel. The cotainer may be magetized though if the field is static or DC pulsed... it would perhaps be just as useful just to make some thing with pockets to put the floppies in, that are made so that the floppies do not come close to the motors.

EvilBob
2005-Jul-12, 01:23 AM
it would perhaps be just as useful just to make some thing with pockets to put the floppies in, that are made so that the floppies do not come close to the motors.
Yeah, that's probably what she'll end up doing, while we wean her off her dependence on floppy disks...

Pinemarten
2006-Oct-14, 04:32 PM
I had a similar mystery once. I realized putting a floppy in the same pocket as my flip phone rendered it unreadable. Flip phones have a small magnet to operate the 'open' switch. Did she have a flip phone in the same bag?

Pinemarten
2006-Oct-14, 04:38 PM
I had a similar mystery once. I put a floppy in the same pocket as my flip phone and it became unreadable. Flip phones have a small magnet to operate the 'open' switch. Did she have a flip phone in the bag?

ASEI
2006-Oct-14, 04:44 PM
Use CDs. They're far faster to write, store more, and they aren't damaged by any random magnetic field. If you leave them out of strong direct sunlight, they're more durable and last far longer.

I just pulled files of a four year old backup CD. Could you pull anything off a four year old floppy? Every time I've tried that, every other file was corrupted, or it wanted you to reformat.

CDs and DVDs. It's all about the optical disks.

Bearded One
2006-Oct-14, 05:02 PM
I used floppies for many years without problems. I have 15 year old floppies that can still be read. Floppies were a viable and good recordable medium. If you have nothing but problems nowadays then I would look somewhere else. Windows has had (has) bugs in it's handling of floppies that cause perfectly good floppies become "unusable". Usually claiming it can't read sector 0. Rebooting the computer and taking a bulk demagnetizer to the disk miraculously makes them perfect again :eh:

mugaliens
2006-Oct-14, 07:08 PM
Solution: Thumb Drive.

mugaliens
2006-Oct-14, 07:20 PM
THUMB DRIVE.

Practically impervious to magnetic fields and stores a whole lot more data.

01101001
2006-Oct-14, 09:52 PM
THUMB DRIVE.

Deja vu (http://www.bautforum.com/showpost.php?p=437810&postcount=3)


Might be time to upgrade to a USB thumb disk.

JohnD
2006-Oct-15, 10:23 AM
A long way back, hippietrex found damaged discs after a commercial flight.
She blamed the security measures - metal detectors etc.
How high and how long would you need to fly for cosmic radiation to be a problem?

John

Spacemad
2006-Oct-15, 12:24 PM
About the duration of data on floppies. I was intrigued, after reading through all the posts anterior to this one, to see if the floppies we still have conserve their data intact. So, I searched out the floppies I had made on our first computer at least 10 years ago. I popped a couple in the floppy drive & had no problems extracting the data they contain.

While looking for my floppies I came across a boxful of floppies our daughter made when she was attending a computer course - back in October 1994!!! I popped one into the drive - lo & behold they are as good as the day she recorded them in 1994!!

All these floppies were made in Spain & brought to the UK 5 years ago. They all passed through airport scanners. Some of my floppies have passed through airport controls on at least 3 occasions. After the initial journey to England I also took a few back with me 3 years ago. The old computer still works but doesn't have a CD/DVD drive. I had copied the files for a book I was writing to a couple of floppies & brought them to the UK. As I was still working on the book I thought I would take some time to continue with my writing while on holiday, which I did. The floppies functioned perfectly on the old machine & I was able to copy the new files back to my new machine when I returned home. I've just opened them again after 2 years & they still work just fine. I have seen no sign of corruption or loss of data!

GDwarf
2006-Oct-15, 12:26 PM
That's actually pretty amazing, since floppies tend to corrupt data if they get too close to even fridge magnets.

weatherc
2006-Oct-15, 01:03 PM
I find that CD-Rs and DVD-Rs work fine for short term storage or for transporting information from one location to another, but for long term storage, these disks are far from archival.

I have run into the problem of losing data on various brands of media of varying quality, and burned with a number of different brands of burners, and burned at various speeds.

It seems that some sort of oxidation can occur with CD-R/DVD-R media, even when the disks are kept in a cool, dark place. It doesn't usually trash an entire disk (unless it affects the leader information that identifies what the disk is to the computer, in which case, it's gone). I usually only lose a couple of files per disk, but that's a couple of files too many.

Sure, there are some disks I have that haven't gone bad in almost ten years. There are others that were burned at nearly the same time with the same equipment that don't work anymore.

In other words, do not trust CDs and DVDs as archives.

And relating to the OP: I haven't had a floppy drive installed on a computer since 1998. Considering how reluctant computer manufacturers are to let the floppy go the way of the dinosaurs, I'm surprised that computers don't still ship with the 5" floppy drives. Hey, you just never know when someone will bring you a 5" floppy that you'll need to pull information off of, right? :cool:

mugaliens
2006-Oct-15, 03:40 PM
Spacemad, in keeping with your quest, I pulled a 360k floppy drive out of the closet and installed it into my computer, then read a disk I'd written in 1985 on a PC XT clone.

Not a problem.

After ten such tries with various disks, however, I realized that disks do have a shelf life: about a third of the disks wouldn't read.