Long term effect of magnet closures on X51 cases

10-25-05, 09:25 PM

Hi,

I did read a post here about there being no effect on the X50v VGA screen with regards to case magnet enclosures ie. Sena, EB

Just wondering if anyone here has had one for a while and can tell me if they've noticed any effects the magnets have had on their VGA screens.

I know if I hold a magnet up to my CRT computer screen, I see a darkening spot, but if I hold it up to my Laptop LCD screen, I don't see any effect.

But I think I read somewhere here, that another Poster's X51v screen went bad because it was too near their computer screen.

Thanks in advance.

**Frenchy** · 10-25-05, 09:40 PM

A guy at work has one and it doesn't do anything to his device. He has been using it for over a year.

Gigi · 10-25-05, 10:47 PM

I've been using my Sena with my X50v since January and my screen's been fine. I've only used cases with magnetic closures on all of my PPCs (X5, X3i, X30) and have never had a problem.

10-25-05, 11:01 PM

Thanks,

I just checked on Dell's site and they themselves sell a magnetic closure flip case for the x50/51v, so I guess it's not a problem.....

Yukster · 10-26-05, 05:12 AM

Besides the screen, would magents affect anything else, like the CF/SD cards, or the RAM/ROM?

donka · 10-26-05, 05:50 AM

I've been using magnetic closure since my Jornada with a magnetic Vaja case - about 4 years. Never had an issue with the device or media.
I currently use Sena and rate them very highly....

bigbop · 10-26-05, 07:53 AM

VGA CRT displays use magnetic deflection to move the electron beam across the face of the screen. That is why bringing a magnet close to the face of the screen will move the electron stream. You can also permanently magnetize the shadow mask so that you get an area that has weird colors, so don't place magnets close to your CRT screens.
A little known fact: keep all sensitive electronic devices away from the CRT when you degauss the screen. The degauss coil can induce unwanted voltages in devices that are either sitting on top of or directly beside the display, possibly causing damage.

As for LCD displays, they use what's called nematic crystals http://electronics.howstuffworks.com/lcd.htm/printable suspended in a liquid. When an electrical charge is placed through the liquid, the crystals align themselves and the cell either blocks light or lets it through depending on the technology used. The crystals are not affected by magnetism.
As for placing you Axim close to a large older CRT display that has a screen acceleration potential of probably 30,000 volts on the faceplate (place the back of your hand close to the screen and watch the hair stand up!), you stand the chance of drawing a high voltage static charge which 'might' cause damage to the device. Not all CRT displays exhibit this though but why take chances. Large LCD displays are low voltage devices so there is no problem there.

As for flash memory, they work on retaining a charge in a cell that represents a specific data state. Since static electricity can damage any electronic device, always take the proper precautions when removing and inserting the parts into your equipment (ie: don't walk across a carpet in wearing nylon socks and pick up your Axim from the top of your CRT! Zzapp!);)
Hope this explanation helps some.

Pocketbrain · 10-26-05, 11:00 AM

Thanks, BigBop, you beat me to the punch.
And yes, the degaussing routine features violently-shifting magnetic fields, which can induce electrical currents in nearby electronics, so stand back with your Axim!
(current through a load = voltage)

Xelkos · 10-26-05, 12:57 PM

Too bad the magnetics couldn't increase WiFi range.

I wonder if sliding a thin copper plate behind the Axim would increase WiFi range... hmm... where's my static grounding strap, I have an idea!

Zero_DgZ · 10-26-05, 04:32 PM

No, if anything that'll absorb a little radio energy and decrease your range. Realistically it'll do nothing measureable, though.

greyseal · 10-26-05, 04:53 PM

Originally Posted by Yukster

Besides the screen, would magents affect anything else, like the CF/SD cards, or the RAM/ROM?

I read an article on this last year -- I wish I could remember the link. But they were happy to note that it would require a magnet "strong enough to pull the iron from your blood" to alter the data stored on any Flash RAM device.

Not sure if the same holds true for the ROM, but your CF and SD cards are safe.