UmTRXv2 samples expected shortage

Jean-Samuel Najnudel - BJT PARTNERS SARL jsn at bjtpartners.com
Wed Oct 31 18:46:47 UTC 2012


Hi Andrey,

Do you think it will be possible to decrease the power consumption and to
keep the best possible performances for industrial applications ?
I know you cannot be sure about this but I would like to know how confident
you feel about this ?

Best regards.

Jean-Samuel.
:-)


On Wed, Oct 31, 2012 at 7:40 PM, Andrey Sviyazov <andreysviyaz at gmail.com>wrote:

> Hi Jean-Samuel, Alexander.
>
> Tomorrow I'll let you know what possible to make on time.
> And we should set time limit for this.
> For example, next morning.
>
> Best regards,
> Andrey Sviyazov.
> (Sent from my mobile client)
> 31.10.2012 22:24 пользователь "Jean-Samuel Najnudel - BJT PARTNERS SARL" <
> jsn at bjtpartners.com> написал:
>
> Hi Alexander,
>>
>> Thank you very much for your reply.
>>
>> Why skip/populate LMS power supply block ?
>> As I understand we always need the LMS power supply block. I probably
>> missed something. Could you explain this in more details to let me better
>> understand ?
>>
>> Thanks a lot for your help.
>>
>> Best regards.
>>
>> Jean-Samuel.
>> :-)
>>
>>
>> On Wed, Oct 31, 2012 at 7:14 PM, Alexander Chemeris <
>> alexander.chemeris at gmail.com> wrote:
>>
>>> Yes, lesser input voltage range makes sense only if it saves >$10
>>> and/or considerably increases power efficiency. I think this not the
>>> case, and then only these changes will be needed:
>>>
>>> * traditional power connector
>>> * MCX RF connector, because they sustain much more connect-disconnect
>>> cycles
>>> * lower power consumption mod
>>>
>>> I would appreciate if we could keep the same PCB for both versions and
>>> populate the proper version of power connector/RF connector and
>>> skip/populate LMS power supply block.
>>>
>>> On Wed, Oct 31, 2012 at 9:56 PM, Jean-Samuel Najnudel - BJT PARTNERS
>>> SARL <jsn at bjtpartners.com> wrote:
>>> > Hi Alexander,
>>> >
>>> > This would be much easier to have the same board for both lab and
>>> > deployment. Only the UmSEL would make the difference.
>>> > For deployment, I really need wide input voltage range as I plan to
>>> power
>>> > the whole system (UmTRX + PA) with a single 28V supply.
>>> > Even if this can save a few euros, I would really prefer we do not
>>> make the
>>> > input voltage range smaller.
>>> > By the way, even for lab, it might be convenient and it can avoid
>>> damages in
>>> > case of wrong voltage supply.
>>> >
>>> > Best regards.
>>> >
>>> > Jean-Samuel.
>>> > :-)
>>> >
>>> >
>>> >
>>> > On Wed, Oct 31, 2012 at 6:50 PM, Alexander Chemeris
>>> > <alexander.chemeris at gmail.com> wrote:
>>> >>
>>> >> Andrey, how much time do you need to create 2.1? If it's mire than a
>>> day,
>>> >> we should postpone this. I believe that enclosure is a much more
>>> important
>>> >> issue at this moment.
>>> >>
>>> >> I think we need following changes for the lab version:
>>> >> * traditional power connector
>>> >> * MCX RF connector, because they sustain much more connect-disconnect
>>> >> cycles
>>> >> * lower power consumption mod
>>> >> * smaller input voltage range (only if this makes things cheaper)
>>> >>
>>> >> Sent from my Android device.
>>> >>
>>> >> --
>>> >> Regards,
>>> >> Alexander Chemeris
>>> >> CEO, Fairwaves LLC
>>> >> http://fairwaves.ru
>>> >>
>>> >> 31.10.2012 14:05 пользователь "Andrey Sviyazov" <
>>> andreysviyaz at gmail.com>
>>> >> написал:
>>> >>
>>> >>> Hi Jean-Samuel.
>>> >>>
>>> >>> First of all, you didn't said about delay duration :)
>>> >>> I can't delay this batch just due to my wishes that each next batch
>>> >>> should work more and more ideally.
>>> >>>
>>> >>>> These modifications looks interesting. I think it is a good idea.
>>> >>>
>>> >>> Hope so.
>>> >>>
>>> >>>>
>>> >>>> I just have a few question.
>>> >>>>
>>> >>>> Why do you call this board revision 2.1 "a special batch for labs" ?
>>> >>>> Would these modifications make this revision 2.1 also more suitable
>>> for
>>> >>>> field deployment, at least as much as the revision 2.0 ?
>>> >>>
>>> >>> Because of I can fix only known issues.
>>> >>> Also not all really required improvements are known yet.
>>> >>>
>>> >>>> Decreasing power consumption to 10..11 W would be great. Is there
>>> any
>>> >>>> drawbacks of this modification ? Would it decrease some
>>> performances ? If
>>> >>>> not, this modifiction to decrease power consumption is a
>>> significant very
>>> >>>> good modification.
>>> >>>
>>> >>> Decreasing of performances it is only spurs with DC/DC conversion
>>> freq
>>> >>> ~500kHz.
>>> >>> Now I searching more good LC filter to suppress it better than
>>> TI2012U601
>>> >>> can.
>>> >>>
>>> >>>> Do you have enough space on the board to replace some U_FL
>>> connectors
>>> >>>> with MCX connectors as you suggest ?
>>> >>>
>>> >>> Yes, but may be not all should be MCX.
>>> >>> Of course I did not insist, but just asking whether there is a
>>> reason to
>>> >>> do it or not.
>>> >>>
>>> >>>> An external LNA would probably need around 5 Volts instead of 6V. A
>>> >>>> small PA would probably need a little bit higher voltage. Do you
>>> think it
>>> >>>> would be possible to have a variable voltage low power connector ?
>>> >>>
>>> >>> On my opinion, variable voltage is not good idea.
>>> >>> For example for LNA's better to place low noise LDO 6V to 5V near to
>>> IC's
>>> >>> to get Vcc clean too.
>>> >>>
>>> >>>> By the way, could you pelase also add the 2 LMS output matching
>>> >>>> capacitors we need to improve output power figures in the 1800 band
>>> ?
>>> >>>
>>> >>> Of course, because it is issue which should be fixed, but not
>>> >>> improvement.
>>> >>>
>>> >>> Best regards,
>>> >>> Andrey Sviyazov.
>>> >
>>> >
>>>
>>>
>>>
>>> --
>>> Regards,
>>> Alexander Chemeris.
>>> CEO, Fairwaves LLC / ООО УмРадио
>>> http://fairwaves.ru
>>>
>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/umtrx/attachments/20121031/5ab72a29/attachment.html>


More information about the UmTRX mailing list