dr_frost_dk | # 11 | 2011-08-19, 14:58 | Report

Fix:

well you can open a working N900 and apply 2 component glue and make the usb much much harder to break off.

you can solder a half broken usb back on, and also use glue to ensure that it stays.

in case of bad break you can make connections from usb to components nearby, this requers small wire and good soldering skills and eqiptment.

finally if you add components (potection) you can make a new usb via the points under the battery, this will be more tricky to do, but if done properly it should work.

dr_frost_dk | # 12 | 2011-08-19, 15:00 | Report

my solution for long lasting usb is that i have a seperate charge port, my battery thread for more info

abill_uk | # 13 | 2011-08-19, 15:21 | Report

IF you want your usb port to last as long as your device then you MUST take it apart and solder both sides of the port itself down to the earth plane.

This will make sure it stays put and please note if you do not do this then it is absolutely positive 100% guaranteed the port will break off at some point.

The reason it breaks off is because the jacket of the port which is all metal by the way is just not soldered down enough coming out of production and as for QA... hahahaha dont make me laugh please.

No special soldering equipment needed to do this as you do not have to touch the rear data tracks if the port is not loose, but i would for the hell of it re-solder the data pins, all 5 of them, just to make sure.

PS i will tell you all yet again ... it is FAR FAR easier to re-solder this usb port BEFORE it breaks off rather than wait untill it is off the board as then it becomes a nightmare for some people to even attempt to put it back in place and solder it.

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Last edited by abill_uk; 2011-08-19 at 15:24.

Estel | # 14 | 2011-08-19, 15:29 | Report

Phone designers will not use separate plug for charger, cause - due to EU and China agreements - every major manufacturer is obliged to use microUSB plug for charging (the infamous agreement on making all phone chargers working with all phones).

Anyway, there *is* solution to fix USB port *before* it's broken - it require disassembling of N900 (not so hard), then, scratching a little solder mask near USB port, until You reveal some cooper behind it. The thing is, that in N900 multi-layer PCB, actual "paths" are between 2 solid "shielding" cooper plates. So, you just solder USB port to that revealed cooper plate shield. Best, when You do it from *both* sides of USB port.

Then, as dr_frost_dk mentioned, it's good to glue it with good epoxy. Such approach should effectively protect port.

Another thing mentioned by dr_frost_dk - DIY external charging port - is good thing, but only if You use mugen cover (well, You *can* take out separate cables with normal cover, but it doesn't look so pretty, and guys in airport security may throw You to the floor with knee on Your neck, after seeing that ). ho ever, it also have some disadvantages - you need to have dedicated li-ion charger (*not* 5V power supply!), and charging goes totally around fuel gauge chip. So, forget about charging calibration.

Also, with external port You should not charge to full during usage (charging to ~80% is ok), because charger will not distinguish current used by phone for operation from current accepted by battery = will charge battery too much, or keep it in "charging forever" state, where current put is equal to current draw by N900. This is very unhealthy for battery, li-ions of all types hate to be "charged forever".

dr_frost_dk | # 15 | 2011-08-19, 15:31 | Report

Also what abill_uk said, this will also help, i still recommend 2 component glue if you want to be totally rock solid, JUST be careful not to get it in the USB port it self, then you will never get a USB in there anymore.

Even if it is soldered down, you can still rip it off by ripping the copper lanes off or breaking them, but of course if you do this then you can never claim to be gentle with you USB port , because this will seriously take some force to do.

But to make a stronger USB just solder it down like abill_uk said, only the big sides of course, i will just do this on the new one i just got and post pictures, in the next hours that is.

Mentalist Traceur | # 16 | 2011-08-19, 15:48 | Report

Keep in mind that people whose ports do not break off don't regularly go around making posts complaining about how wonderfully reliable their USB ports are, so it'll always seem like a more pernicious problem than it is.

I'm one of the proponents of the 'different hardware batches' interpretations of the problem. I don't remember where I saw what posts, but the same people have had different N900s with drastically different USB port strengths/durability.

There are people who report abysmally flimsy USB ports that failed even with delicate treatment, and then there's people who regularly yank their N900s around by the USB cord when plugged in, and have no problems. Either a large portion of this community is made up of people who lie, don't know their own strength, or suck at describing anything, or we have to accept that some USB ports aren't as flimsy as others.

Texrat | # 17 | 2011-08-19, 16:09 | Report

Read the descriptions of the issue-- it's not an easy fix. This is surface-mount technology.

The permanent fix was in Nokia's ball court.

I still recommend epoxy. Additional solder may not help on poorly-tinned connectors.

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Last edited by Texrat; 2011-08-19 at 16:16.

Texrat | # 18 | 2011-08-19, 16:14 | Report

On the other hand, I went to great effort to solicit feedback from N900 owners and got a great response in general, including from those not having any problem. They were more than willing to help.

I'm confident that, over time, the high failure rates cited are accurate enough.

http://tabulacrypticum.wordpress.com...-do-something/

NIN101 | # 19 | 2011-08-19, 16:25 | Report

I had hope after I read this, but then..:

http://talk.maemo.org/showthread.php...84#post1063784
http://talk.maemo.org/showthread.php...65#post1071665

I have hardware revision 2104. I know two guys with my this revision whose N900 lasted over one year/1,5 years so far and they say the usb port seams to be fine. One didn't file the hooks on the connector and the other says his original cables don't have hooks... which is pretty interesting if true. This is my second N900, my first died after ~6 months, unfortunately I don't know the revision of that, the question is if the hw revision matters at all. Given what I have read: No.

As I am a complete noob at soldering and my N900 is still under warranty , the only thing I can do is to file down the hooks and don't move the N900 while it is charging. I hope it'll live long enough (say 2-3 years) with this handling.

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Last edited by NIN101; 2011-08-19 at 19:50.

abill_uk | # 20 | 2011-08-19, 16:29 | Report

Is easy to tin the jacket, just scrape it with a needle if need be and use solder flux or solder acid to make sure the solder "tins" the metal soldering it down to earth before you epoxy it but i still feel epoxy is messy and has a life span before going brittle and cracking up.