Hello People, and enormously huge excuses for not replying sooner.

I know that I should do it sooner, and for a fact, despite that real
life was *very* absorbing last few months, there is no good excuse for
not contacting - i just *should* have find a piece of spare time, no
matter what, to write at least few words, considering circumstances
(your support for replacement backcover/body project). I can just
apologize, again.

That said, project is alive and I haven't had plans to cancel it, even
for a second. Unfortunately, it was delayed - I got very serious
things to take care of in my personal life, that not only absorbed
every bit and piece of my free time, but also, forced me to quit a job
for few months and live from savings. Fortunately, everything seems to be heading for happy end, so I resumed my normal activities, from job, to having (some) free time to spend on projects.
---

Now, when it comes to project - it had some bad times, even before my
private affairs started. Someone, who promised professional 3D scans
of regular case internals (for motherboard, contacts, functions, etc)
- that would ease work very much - disappeared without any trace. I'm not criticizing here, as I don't know reasons - after all, not so long after, I was MIA too, so he might have no less important things in real life. Peter, if you're still around, don't hesitate to contact me - your help is still welcome.

Anyway, I had no other choice, than reverse-engineer everything on my own. Still, using small bits of free time that I was able to find, I was
(slowly) proceeding - many times, sparks came through motherboard when inserted to prototyped internals (here, half-dead N900's
motherboards, that kind people have send me, helped a much - no living
motherboard got killed in the process of making it ), but slowly,
it took shape.

Now, since few days, I'm test-driving pre-pre-pre-pre-pre alpha
version of case. Externally, it doesn't have any user-interface
functions (aka holes for ports, speakers, or even keyboard -
basically, it doesn't have anything on the outer side, and looks like a
brick of aluminum.

Hoever, inside, it have most shapes required to properly cooperate
with motherboard - ground plane connectors, blockers for
spring-connectors, supports (to avoid bending of MB), and connectors
for antennas (although, currently, anything beside wlan0 is dummy).
Despite usage in different temperature conditions (from regular ~20 C
degrees, to -20 C degrees, outside, before battery decided to shut
down power) and some rough times with it, no sparks, shortcuts, or
connector slipping, finally.
---

Now, I won't hide, that there is still *much* work to be done, and it
will be delayed more, for no doubt. But, slowly, it's taking shape,
and I really hope, that we'll be able to enjoy results in N900's
lifetime (considering, that still no proper replacement for N900 on
horizont - and I mean Jolla here, too - that shouln't be too hard...)
---

Now, a word of warning. While I decided to shake my hand at whole Maemo politics and actively participate in TMO discussions, about projects that interest me, i'm still not sure, if TMO is safe/friendly place for work coordination, anymore.

After all, moderator who broke basic rules - like using anti-spambot one-touch ban and clean against living user (one with positive thanks/posts ratio, too), banning him eternally and deleting all of his contributing posts to TMO, for no real reasons - is still around, probably, feeling more allowed to do whatever he want, than before.

If anyone is interested on background for this whole mess, everything is explained on (long) discussion on mailing list, starting from this entry:
http://lists.maemo.org/pipermail/mae...er/005696.html

While one need to filter out some flamewar-like or angry messages, every piece of information is to be found in that mailing-list thread.
---

Now, frankly, I suppose, that most of you don't care - nor do I. If anything pathetic happens again due to rogue moderators or whatever, I'll just give this place a laugh, this time for good, but I won't exit from Maemo, nor this particular project. In case of TMO being unbearable for any constructive thing, I'll set up small independent board, just to keep contact with people interested in this project (and donors, and pre-ordering people, etc). frankly, I planned to do so already, but for obvious reasons (time) decide to scratch it, for now.
---

Apology for long silence, again - it wasn't in my plans, at all, and I'll do my best to keep all of you properly updated on project progress, now.

/Estel

// Edit

As for PM's, excuse no reply, but, during monthly ban, my PM box got full (for obvious reasons). I've cleaned it a little, so it should work again, now.

It's good to hear from you again, Estel.
Not just to inform us about the state of your project, but because I consider you to be a kind person and a valuable member of this community (as in the actual people of maemo.org and not it's management).

Best of luck to you. Even more-so in these bitter times.

Hi.
This is my first post here, I decided to register on board because of some important observation I had on this replacement body idea
(and recently bough used n900 by the way).

I really like the whole concept, and its nice to see that group of people scattered around the globe are able to cooperate to make concept into end product.

But there is one important thing that would make it real "killer" : idea of making external antenna connector. Without internal switch that would disconnect internal phone antenna prior to connecting external one such antenna would make reception worse and/or permanently damage cellular module.
External cellular modems with ability to connect external antenna have switch built in connector itself (like huawei modems with CRC9 connector). UF.L connector on n900 does not offer such functionality. UF.L can be found also on internal wifi and cellular modems for notebooks.
Last time someone did disconnected (accidentally) one of antennas on my dell tablet-pc while it was working I ended up with dead 3g modem. So this is not just an theory for me.
Without proper switch body with external antenna connector = nice looking and expensive make-your-n900-useless kit.


That was important part I didn't write this to criticize, only to save some n900 from sad end. Also discovering this issue after making working prototype would definitely slow down progress on developing aluminum body.
Now some constructive ideas :

-Why bother making full milled alu body? It would be expensive and slow to manufacture. Maybe it would be cheaper to order/make press stamp for thin internal body part made of aluminium sheet, and glue it with milled wooden external shell? It would be sturdy, safer*, elegant and since internal part would be unified - making custom external shell would be faster and cheaper.

*(in event of body falling from height wooden part would shatter thus disperse kinetic energy of blow, and elastic aluminum would keep phone internals from falling outside)

-Mugen battery is fun, but it does not make space efficient solution. N900 its already considered an brick. Make it thicker and it would be perfect building material...
How about adding small housing for 9V alkaline or li-ion battery? Take 9V battery and n900, see it does fit perfectly, there is enough space for simple dc-dc converter to make it usable voltage (3.7V). Such housing wouldn't make n900 any thicker, just slightly longer.
Stock N900 battery can supply of 3.7V*1.322AH = 4.9 Wh. Now 9V alkaline can be found with capacity of 550mAH, that gives 4.95 Wh. Double your battery life cheap, and get power-source independent at same time.
Of course there are 9V rechargeable batteries, but those aren't so great, but i can imagine custom body can have option of attaching 9V housing from both sides

PS> Sorry for my english, its not my native language and I didnt write anything in it for some time.

the back cover can be printed with a 3d printer?

Thank you for interesting ideas, hamil_hamster!

As for your worries about externall antenna, I'm not sure why your modem got damages during *disconnecting* ext. antenna accidentally, but I would rather said about static burst during unexpected separation. I'm testdriving N900 with antennas connected externally (without sacrificing built-in ones), and I'm not experiencing symptoms you've described. I think it depends a lot on externall antenna design - having background in those things, I use my DIY fractal sets, adjusted to frequency I need at the moment. I haven't observed any negative copling between it and internal antenna, as long as everything that should be shielded, is.

Of course, it will require some sanity from user - connecting to-be external antenna port to lightning strike catcher isn't best idea, for sure Still, it will be "just port" - no one forced to use it, and when not in use, it won't result in much difference from having those hirose ports on motherboard (which every N900 got).

As for stamping internals, it's very interesting idea, but I don't have access to such tools - and, ordering it from somewhere near me, require huge quantities (or insane price).

I don't expect ever selling hundreds of them, so CNC milling, while not-most-effective for large quantities, seems best fit for this project scale.

/Estel

@Estel
Im glad that you tested n900 with attached antenna and nothing bad happened. Just to be scrupulous on subject some testing including comparison of reception when external and internal antenna is connected, and when only external antenna is connected would probably clear all doubts. If it isn't instant death situation for N900 then I might try it my self some day
To be thorough on subject I must add, that modem of my dell computer wasn't only time I encountered issue of two antennas connected to one GSM module, recently did some search on work-around on damaged antenna connection in Huawei e3131 modem. In work-around solutions I found it was stated that internal and external antennas circuits should be connected at same time, only one of those work-around repairs at the time should be applied.
Before proceeding to make repair my self I asked some questions about why it is that way and what can be done to have options of using both antennas, my loose translation of received answer : if external antenna would be connected without internal antenna disconnected it would result in change of antenna path impedance and neither antenna would work properly. In worst case scenario it may result in burning antenna* amplifier (* - antenna or power amplifier, cant distinguish which translation of polish "końcówka mocy" is correct).
Reading thread " Fixing USB port, before and after it is to late. " I found information that you are also from Poland, so here is thread on polish electronics board I'm refer to http://www.elektroda.pl/rtvforum/topic1691248.html
Apparently this is real issue involving multiple 3g modem models, not only this one.

But electronics in mobile phones might just be little more tolerant for abuse.

As for ordering custom parts, now I understand why you made CNC yourself, anything involving prototyping is ridiculously expensive here. Its cheaper to order part from another part of globe (like emachineshop) than from small machine-shop next-door.

@Estel
I'm glad that you tested n900 with attached antenna and nothing bad happened. Just to be scrupulous on subject some testing including comparison of reception when external and internal antenna is connected, and when only external antenna is connected would probably clear all doubts. If it isn't instant death situation for N900 then I might try it my self some day
To be thorough on subject I must add, that modem of my dell computer wasn't only time I encountered issue of two antennas connected to one GSM module, recently did some search on work-around on damaged antenna connection in Huawei e3131 modem. In work-around solutions I found it was stated that internal and external antennas circuits should be connected at same time, only one of those work-around repairs at the time should be applied.
Before proceeding to make repair my self I asked some questions about why it is that way and what can be done to have options of using both antennas, my loose translation of received answer : if external antenna would be connected without internal antenna disconnected it would result in change of antenna path impedance and neither antenna would work properly. In worst case scenario it may result in burning antenna* amplifier (* - antenna or power amplifier, cant distinguish which translation of polish "końcówka mocy" is correct).
Reading thread " Fixing USB port, before and after it is to late. " I found information that you are also from Poland, so here is thread on polish electronics board I'm refer to http://www.elektroda.pl/rtvforum/topic1691248.html
Apparently this is real issue involving multiple 3g modem models.

But electronics in mobile phones might just be little more tolerant for abuse.

As for ordering custom parts, now I understand why you made CNC yourself, anything involving prototyping is ridiculously expensive here. Its cheaper to order part from another part of globe (like emachineshop) than from small machine-shop next-door.

Would it be possible to add slot for memory bank? (Connected to n900 motherboard properly).
It would be cool to have 1.2GB ram in N900 working (256MB internal + 1024MB in-cover)
I hope n900 to be electrically compatible with notebook memory banks (or else it would need special parts which would be accessible only in large quantities)

anyway is it ever possible?

Other insane idea is to include miniature usb hub on the left to split between full sized usb port and builtin usb to ethernet adapter.

Third insane idea is to include minijoy and 3 buttons on the right connected to said before usb hub as usb mouse (+ probably another full-sized usb port)

Having seen inside the N900 I doubt there is space for any of this.
Also there are other solutions.

Using Thumb and Swap on SD will help the lack of memory issue.

http://talk.maemo.org/showthread.php?t=84829

USB Hubs could be used from the micro USB (be careful to reinforce the port if your using it a lot)

Bluetooth with extkbd and extmou is much easier.

http://talk.maemo.org/showthread.php?t=85658
http://talk.maemo.org/showthread.php?t=65577
http://talk.maemo.org/showthread.php?t=66141

Have you seen the internal size of a full size USB, there are also reasons why they are not used.

http://talk.maemo.org/showthread.php?t=86279

Unfortunately, it's completely different technology, and it's absolutely impossible to use RAM sticks in N900. See wiki page about N900 hardware - memory is part of SoC.

We can't add more separate USB port to N900 - any addition would be just another plug for same physical port, so not possible to use 2 different devices at the same time.

I thought briefly, about using micro-hub inside (that would, indeed, allow to connect more than one device at once), but it would be infeasible due to size (less important), and increased battery drain, when hostmode is active. It's just much better to connect small, external hub, when you need it.

BTW, it was discussed in this thread, already.

/Estel