Broken component on motherboard

[PteroWarrior]

Hi all,

some months ago i burned my belowed TX...

It's still working but I passed some scary moments when i saw white smoke coming out from the case.

In the beginning i thought it was an electrolityc Capacitor
but looks like some diod

I attached some pics of the component

Can you please give me some advice?
Is there a place where to find some schematics?

Thanks

[raspabalsa]

Hi all,

some months ago i burned my belowed TX...

It's still working but I passed some scary moments when i saw white smoke coming out from the case.

In the beginning i thought it was an electrolityc Capacitor
but looks like some diod

I attached some pics of the component

Can you please give me some advice?
Is there a place where to find some schematics?

Thanks
That component is a capacitor, not a diode. Check this thread (http://forum.brighthand.com/showthread.php?t=239291) at Brighthand, there you will see hi-res pics that will let you identify it. The capacitor is labeled just like the one next to it: 150 4V, which means 150 uF, 4V. The white band means it's polarized, just like any electrolytic cap.

Do you know how this component got burned? From its location on the board next to the headphone jack and being that there are two identical ones, looks like it's part of the audio output circuit. Have you tested sound output through headphones?

I haven't seen a schematic for the TX, and I don't think there are any readily available. But with the component data you can start scavenging other mainboards and see if you can find one. If youcan't locate one rated 4V, then try to find one with higher voltage rating.

[PteroWarrior]

Hi Raspabalsa, many thanks for your prompt reply and for the link

Yes, I was thinking of a Capacitor, but i had some doubts.

Indeed I know how the component broke and you're right it is related to audio.
Basically it has been a ground loop with the hearphone output.
The car power supply was broken, i inserted the hadphone jack to connect the palm on my car stereo (when i drive i use it as GPS and mp3 player).
I realised that inserting the audio jack the power supply went on.
As soon as i noticed i tried to remove the audio jack but it was too late.

Anyway even the audio output is working properly.

That was during july 2009.
Unfortunately in the latest months i'm starting to experience some instability (such as PalmOS resets, wifi broken, loosing configuration data etc)
Don't know if it is somewhat related to this incident.
In the beginning i thought about some "brown out" due to the fact it miss a capacitor...

Don't know if to try to change the broken capacitor, remove it or leave as it is.
I'm quite used to solder smd components, and this one is one of the few big enough to be handled

Thanks Again

[raspabalsa]

You're welcome, PteroWarrior
Indeed I know how the component broke and you're right it is related to audio.
Basically it has been a ground loop with the hearphone output.
The car power supply was broken, i inserted the hadphone jack to connect the palm on my car stereo (when i drive i use it as GPS and mp3 player).
I realised that inserting the audio jack the power supply went on.
As soon as i noticed i tried to remove the audio jack but it was too late.

Anyway even the audio output is working properly.
The two caps seem to be filters, so probably you'll just notice some hissing in one audio channel.
Unfortunately in the latest months i'm starting to experience some instability (such as PalmOS resets, wifi broken, loosing configuration data etc)
Don't know if it is somewhat related to this incident.
Easiest way to troubleshoot this is to do a hotsync and a backup to card (with NVBackup, RescoBackup, or any other similar program), then do a hard reset. Do not restore or install any program yet. Run a series of tests trying to replicate the errors and instabilities you've seen. If none appear, restore your data little by little. Act as if you were upgrading your device. Read this thread (http://forum.brighthand.com/showthread.php?t=220374), there you will find instructions to do this. Keep testing all along, and reinstall your programs one by one. It will take several hours, but will let you rule out the possibility of hardware failure.

If the TX exhibits the same errors right after the hard reset, before you install anything, then most probably there is some serious hardware damage.
Don't know if to try to change the broken capacitor, remove it or leave as it is.
I'm quite used to solder smd components, and this one is one of the few big enough to be handled
If you're handy with SMD's, then go ahead and change it. I've soldered SMDs on my TX and several cellphones, and I don't even have the proper tools to do it (I use my Weller 15W needle-tip iron).

[PteroWarrior]

Hi,
thanks

yes, I'm using NVBackup since many years ago and I'm used to restore the TX as you are suggesting me.

I'm afraid this time there is some serious hw problem, maybe some memory location is damaged, don't know.

I solved partially the issue by de-soldering the battery, but sometimes strange things still happens.

If the TX would become unusable maybe I'll switch back to my Vx
IMHO Nowadays new generation PDA sucks...

Ciao

[sweller]

Bummer! You probably mortally wounded it.

If it comes down to it (It sounds like it will), a replacement MB is $95:

http://www.usedpdaparts.com/PalmTX.html

Pretty reasonable when compared to some of the other alternatives.

I'm actually thinking I should get a couple of everything that I'll need to keep mine alive after they've faded into oblivion. There's just no substitute for a TX.

Steve in NM

[raspabalsa]

I solved partially the issue by de-soldering the battery, but sometimes strange things still happens.
I guess then it's best if you try three things at the same time: disconnect the battery, replace the burned cap, then do a hard reset. If after reconnecting and before installing anything the TX still misbehaves, then it's damaged mainboard alright.
If the TX would become unusable maybe I'll switch back to my Vx
You're seriously considering this? The Vx was my first Palm, and although it was a great device 9 years ago I know I wouldn't accept using one as my main PDA today.

Replacing the mainboard as suggested by sweller seems a better, if somewhat expensive, alternative.
IMHO Nowadays new generation PDA sucks...
Agree wholeheartedly. Add to that there are no new standalone PDA devices means that I too will probably start hoarding TX spares.

[PteroWarrior]

Nice to see I'm not alone in the universe (regarding my opinion about PDAs)

Just to give an example on what i mean when i say "strange behaviour"
this morning i found different applications than usual on page 2 of the launcher application
and since last week i get reset each time i switch on wifi (i didn't installed anything new)

thanks also for the link on pdausedparts
are they affordable?
95$ can be a good bargain to recover my palm (and since i also have a spare display+digitizer i could use the broken parts for experiments)

Ciao

[raspabalsa]

Just to give an example on what i mean when i say "strange behaviour"
this morning i found different applications than usual on page 2 of the launcher application
and since last week i get reset each time i switch on wifi (i didn't installed anything new)
These extra programs must be hidden ones that for some strange reason got their hidden attribute set to on. As for the WiFi, could be corrupt preferences. I think you should go the hard reset + battery disconnect route. If the problem persist, then change the mainboard.

Or, contact Shawn Lux from usedpdaparts, describe the problem and possible cause, and see what he recommends.

[sweller]

thanks also for the link on pdausedparts
are they affordable?
95$ can be a good bargain to recover my palm (and since i also have a spare display+digitizer i could use the broken parts for experiments)
Ciao

I wouldn't go so far as to call it a bargain. But since there are ZERO alternatives to a working TX, that's why I consider it reasonable.

The guy's name is Shawn Lux, and he's highly regarded on Brighthand.com. Do a quick search on his name:
http://forum.brighthand.com/forumdisplay.php?f=1099

He recently took another job and relocated so he's still coming back up to speed. You can send him an email through the website and let him know your situation.

Steve in NM

[PteroWarrior]

did not found the guy you was mentioning.
But in this period $ is quite convenient compared to Euro
I think i'll go ahead and buy the motherboard at least to have a spare part for the future.
at the very end, then i'll consider to switch back on vx
Vx used as agenda and memo is still fine
(but i'm afraid it got the mad digitizer syndrome, i have to check)

For all the rest i'll use the eeePC :D

thank you guys for your help

[PteroWarrior]

Update
Today I just received the motherboard.

I'll change it in the next days

Regards

[sweller]

Excellent!

Out of pure, dumb, curiosity, what was the postage?

[PteroWarrior]

Out of pure, dumb, curiosity, what was the postage?

Unfotunately i had to pay 21€ of custom fees
:(

that is due to the fact the guys stated the price in the package.

Anyway, The TX is alive and well :)

[sweller]

Hmm... Is he *required* to state the Price on the package?

If so, we might look at it this way... He's honest to a fault. ;)