LTE broadband change

[NightNord]

Hello everyone.

I've recently brought an Xperia Tablet Z LTE in Spain. Due to the circumstances I needed waterproof tablet urgently (for maritime navigation). Now I've returned home in Russia and, alas, LTE doesn't work here. No surprise though.

First of all a bit of rant:

A very nice girl in Barcelona's Sony Center was assuring me that tablet comes with 2 years of European warranty and 1 year worldwide warranty. Sure I was fool to belive someone in official clothes in the official store - I shoud have asked some random unrelated people in the Internet as they generally know things better - but anyway, there is no warranty in Russia. Xperia series are supported in country of sale only. Sure, official store employee could not have a slightest idea about that, why would she...

At last I'm now sitting in Russia with tablet which costed me ~x1.5 of the local price, without warranty and without LTE.

And as I lost my warranty anyway (I'm not going to fly to Spain each time I need a repair), I'm trying to fix the thing by reflashing device with local firmwares.

But alas, my model SGP321E1/B supports only LTE bands 1,3,5,7,8, but in Russia we are using LTE bands (700), 7, 20, 38. In other words - flashing firmware won't help. I need to reflash the chip, if it possible.

So, I have a question (probably for Sony representatives): is there any difference between Russian and Spain model in hardware? Are frequences hardware restricted or this is only chip's firmware?

If it's not (and I do belive it's not, as I know people reflashing their Xperia phones all the time. And Samsung supports modem reflashing almost officially), could be you so kind to give me Russian chip firmware? I know that it's a long shot, but who knows - you may just restore my trust in Sony employees 😃

Thank you.

[Uliwooly]

Indeed is hardware not software. 

You can flash other firmwares but that's not going to change the LTE frequencies, again its hardware not software. 

[NightNord]

There is a difference between "firmware" of the Tablet itself (i.e. kernel and the environment, OS is general) and the firmware of the chip. Any modem has a firmware. And in general there are no modems with so selective bands available - it's just impractical to make so many different designs. Most of times WiFi and radio chips are just firmware (chip's firmware, "real" firmware, not OS) restricted to comply with local frequency regulations.

Good thing would be to know exact radio chip model installed - they I could check out official chip manufactorer refence to see what frequences it supports in theory. If there will be no Bands like 20 - then I'll accept "this is hardware" as an answer. If it does - then there always is a way to reflash the modem, either in hardware way (by attaching programmator) or in software way (like in Xperia Z phones, which have "broadband" flashing option or Samsung phones which have "modem.bin" file).

But I'll need a firmware to flash and if that will require hardware intervention - I doubt that I'll be able to convince anyone donating me their hardware (plus chip could be different after all - wrong firmware won't work there).

Plus I do belive in firmware version as you can see modem configuration in the service menu, which clearly shows that there are some configuration files restricting bands.

But someone from Sony could just ask their engeneers and get all the information, saving my time and effort. And preventing me from digging further and finding out how to enable all frequences supported (because I'm lazy, but perfectionst - if I'll start digging, I'll do my best to get most universal solution possible). Imagine cheap Russian tablets invading European market after being reflashed. Sony don't want this, do they?

Consider this a bit of blackmail, if you wish - after all they lied to me, so I have all the moral right to blackmail them back 😜

[Uliwooly]

I still think its hardware not software, an example, there are variants of the iphone for different LTE radios, and this is hardware not software related, but if I see anything I'll let you know, contact Sony perhaps they can give you that info. 

[NightNord]

Thank you. I'll send a message to the Sony support, sure. But in general it's more probable to meet tech guy on forum rather then push your issue though the "first-line" filter of the official support.

AFAIK, iPhone restrictions are semi-software too. It's just hard to reflash iPhones (probably). At least, we have a lot of foreign 4G iPhones on blackmarket (and there is no "white" market) from countries with completelly incompartible LTE bands. But they work well, so anyone who sell them also reflash them.

[Uliwooly · Accepted solution]

developer.sonymobile.com

http://dl-developer.sonymobile.com/documentation/whitepapers/Xperia_Tablet_Z_LTE_WP_4.pdf

it use this modem

MDM9215M

 http://www.qualcomm.com/media/documents/gobi-product-specs

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&cad=rja&ved=0CEIQFjAC&url=http%3A%2F...

[NightNord]

Oh, thank you very much. Now I see this info at the Wikipedia page too (by googling chip model), shame on me.

So, after all there is a hardware support for 800 and 2600 frequences (Bands 7 and 20). And probably chip is the same worldwide. There is no mention of 700 (unspecified) or 2600 TDD (38) frequences though, but I think it should be enough to have two Bands of four supported (of three, actually. 2600 TDD is limited to one city only).

Well, now I only need to find a way to reprogram this chip.

[shanintel]

WHY DON'T THESE SONY MOBILES DON'T OBEDIENT TO ALL FREQUENCIES. We are paying for that only.

[shanintel]

Under estimating me. Will ne all time poster