UmTRXv2 samples expected shortage

Andrey Sviyazov andreysviyaz at gmail.com
Wed Oct 31 21:26:37 UTC 2012


Dogs - FPGA.
Excuse me for my stupid Samsung :)

Best regards,
Andrey Sviyazov.
(Sent from my mobile client)
01.11.2012 1:19 пользователь "Andrey Sviyazov" <andreysviyaz at gmail.com>
написал:

> Hi Jean-Samuel.
>
> About power consumption and performancea I can say that spurs at 500 kHz
> offset around 6dB above TX LO noise plot.
> It wad measured when 3.3V come from dogs through TI2012U601.
> Tomorrow I'll measure all again and share pics in this topic.
> As I mentioned, I'll try to find better filter to suppress 500kHz.
> Please let me know any partnumbers or suppliers you known.
> Also unoccupied place under 3.3V LDO's near LMS seems a good place for
> thermal sensors.
> About rf connectors, now I am sure that MCX much better then U_FL and we
> should return them.
> To connect UmSEL to UmTRX v2.1 required U_FL-MCX cable assemblies till new
> UmSEL version.
> Also possible to use direct cable soldering to UmSEL board.
> Of course, last variant look not perfect.
> About requirements at 400kHz we can't meet, I actually can't understand
> what do you mean.
>
> Best regards,
> Andrey Sviyazov.
> (Sent from my mobile client)
> 31.10.2012 22:47 пользователь "Jean-Samuel Najnudel - BJT PARTNERS SARL" <
> jsn at bjtpartners.com> написал:
>
>> 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
>>>>>
>>>>
>>>>
>>
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