Hello All,
I have been offered a Palm V as a replacment for my broken handspring Visor deluxe. The palm V has the better screen and sure is better looking. The only problem...it only has a 2mb memory chip, whereas the visor had 8mb.
After research, the palm V can be upgraded by adding a 8mb dram chip and removing the 2mb chip. The dead visor thankfully has such a 8mb chip.
The solder points are tiny but I confident that my soldering is good enough. I am just unsure how to detach the chips. ...
Questions:
1. How much heat does it take to toast a dram chip? In other words how heatsensitive are they?
2. If heatsensitve should I try ChipQuik? http://www.chipquik.com/ I dont really want to use this as it could be hard to remove the compound...
3. Some sites say use a heatgun...but I think this would effect other components...so dont use?
4. So finally, just be careful and work around the chips with soldering wick and a tiny iron...?
I look forward to your answers...
Here is a pic:
The dram chip is the one that says SEC KOREA 901. Its the one with the many pins at the bottem of the board.
Cheers
T
I'd researched doing a ram upgrade on my palm or ipaq - during the brief period I owned each respective machine.
Bottom line was, if you've just got a soldering iron and wick, don't even try. You need SMT desoldering equipment, or you'll likely cook something, no matter how careful you are.
I practiced on some Apple 16-meg simms - tall simms with higher density chips that were a bit closer to the DRAM chips than the standard 20 or 24-pin simms. I tried heat gun, desoldering with wick, toaster oven; nothing worked once it was put back together. Only some of the smaller 8-meg simms I was able to fix, because they have longer, thicker pins on the chips.
Some Palm upgrade info here
Note some of the links are dead - it's hit and miss.
Kf you're unsure, don't do it. Google around for a place that will do it for you. I know that www.ipaqrepairs.com charges $89.00 US for this, but I don't know of anywhere that could do it for the Palm. Google around and you probably will find something.
I think I will give it a go. Its been annoying me for weeks... Although my soldering technique is not perfect I have done alot of work on it over the years. I am pritty confident that I can pull it off.
Well we will see
Anyway, its only £20...
unless you own a robotic assebly line, its pretty much imposible. someone did it a while back be recking the old chip making a slide in holder(like what holds the bios chip in on a pc) and putting *i think* a 32 meg chip in its place, so its worth a try if you really dont care about the palmpilot
I'd just jump on eBay and buy a Palm Vx, then sell the Palm V.
here's some stuff to keep in mind:
A) the Visor's already shot, right? So use the heatgun method to strip the 8MB chip off its PCB.
C) if the Visor's ram is shot, you'll be wasting yer time and a perfectly good Palm. You sure that ram's still good?
Finally, as the good Doc Webster suggests, perhaps you'd be better off just finding a nice Vx instead. I've purchased several Palms Vx on eBay, the last one (6 mo. ago?) cost ~US$50 and I'm sure they're even less nowadays. I'm quite sure this last is the most practical approach, but I do appreciate your urge to hack.
:d
Dan K
Desoldered the DRAM chip using my iron, a really thin bit of wire and alot of flux...
I held the iron to each pin of the chip for about 1/10th of a second or less...a lot less than wick would have taken.
All i did was place the wire down the center of the chip and gave it a pull while heating each pin in turn. The wire slides under the solder and pin when you heat the pin, lifting the pin and removing excess solder. It seemed to work fine. The classic way of removing SMT ic's
The chip is now detached with no visible damage to chip or board. I look forward to the palm V arriving.
I hope it work
Thanks for all,
T
Probably not a good idea without using ChipQuick or at least the low temperature solder stuff. Have you checked out any desoldering equipment online? I've got a link somewhere to a .jp rig that uses hot air reflow and a vacuum pickup. I was thinkin' a pyramid shaped heat shield/vacuum pickup tube for the target IC (T-REX) and a larger, but still close fitting inverted square funnel, low pressure heat removal shroud to protect the mobo (2300c/5300c/1MB or 5300ce) might just be workable . . .
Tried and true method to protect the mobo and trash the IC.
Indubitably . . . aaaand . . . the point being? :ebc:
Me too!
NICE TECHNIQUE! Where'd you find info on that method, got linkage, got piccies? Do the pads remain nicely tinned?
Damn the . . . practicality . . . hack speed ahead!
jt
p.s. yo, 'stealth! This thread deserves a more descriptive title/explanation and a move to the hacks forum a/o HackFAQ! I only reas it and chimed in 'cuz I was bored. There's so little activity I read a thread that I normally wouldn't have, given the title.
. . . and where have YOU been, BTW?
•••••
Hey, JT do you still need the info.
Update: I did not manage to try the hack in the end
I sold the screen for £25 to a friend to fix his palm V (profit of £5 lol...what a HUGE profit) and bought a dead palm vx on ebay for the profit i made £5. It had a battery problem. Even with a new battery it would drain in hours when off
Luckily I located the source of the vx malfunction to one of the backlight chips (as the backlight did not work), which was draining the power. I simply removed it (its smaller than the ram!) and the VX fired up fine. As the previous owner had put a new battery in it...its got tonnes of life.
Im pritty chuffed with my £5 palm VX
Now if i can get this m515 to work...
. . . even if I don't intend to use it immediately. Don't knock yourself out looking for it though, but if it's handy, post it! I'm not the only one that'll benefit from it, the forums are GREAT for sharing tidbits.
jt
I've been looking at that 16mb visor upgrade for a while. However i'm not much of a solderer, i'm okay with audio electronics and pipe but IC's don't have the space to work within. Sanyway the visor upgrade is easier in my opinion, just solder another chip on top of the existing chips pins and a jumper wire to the processor.
I've also seen a FLASH ROM upgrade done, 4mb ROM, 16mb RAM in a Visor Prism (16K color). Used some app to put things into ROM, would be really nice to have an expanded program library after a hard reset.
I've desoldered chips like that with heat guns on several occasions. As long as you don't bump anything around it when removing the chip, you'll be fine. As for heat, one chip really isn't more or less sensitive than another in most cases. Since they are assembled by machine over a wave of molten solder, they are designed to take very high heat for a short time. Besides, the new chip won't see very much heat at all.
Thanks for the information Dr Bob
I no longer have the palm V
but I did get a tungsten E for £50...which I think it ok value.
Anyway, hopefully I can fix this tungsten E's power button...and get it running