Yep, I understand...

Good luck!
Sergio

On Tue, Feb 21, 2012 at 9:20 PM, Xiaohui Liu <[email protected]> wrote:

> Hi,
>
> Thanks for your data.
>
> I'm just wondering if there is any one else having similar result with
> yours before I accept it as my ground truth. 4-5 dB's difference is too
> large for my purpose.
>
> Or has anyone got a measurement conforming to the datasheet?
>
> On Tue, Feb 21, 2012 at 12:20 PM, Sergio Valcarcel 
> <[email protected]>wrote:
>
>> Hi
>>
>> We sold a sma connector to the iMote2 board which was connected directly
>> to the spectrum analyzer, through a good and short cable (I assume < 1dB
>> att @ 2.4GHz).
>>
>> I did not use a vector network analyzer to check the impedance... so the
>> only thing I guess now is that we had to move one smd capacitor, which is
>> pretty small, so perhaps it was a bit burned after sold again. Hence the
>> output impedance could be a bit non-matched.
>>
>> I would not be surprised if the iMote is not giving 0 dBm, but some dB
>> less...
>>
>>
>>
>> On Tue, Feb 21, 2012 at 4:45 PM, Xiaohui Liu <[email protected]> wrote:
>>
>>> Hi,
>>>
>>> This is what the datasheet says:
>>> power vs dBm
>>> 3       -25
>>> 7       -15
>>> 11     -10
>>> 15     -7
>>> 19     -5
>>> 24     -3
>>> 27     -1
>>> 31     0
>>>
>>> Somehow your measurement of those power levels is 4-5 dBm lower than
>>> what is shown above.
>>>
>>> Are you using an attenuator over the antenna or measuring the power some
>>> distance away? I'm not familiar with spectrum analyzer, so I'm just giving
>>> some naive guess here.
>>>
>>>
>>> On Tue, Feb 21, 2012 at 7:52 AM, Sergio Valcarcel 
>>> <[email protected]>wrote:
>>>
>>>> Hi,
>>>>
>>>> this is what I measured one and a half year ago using an iMote2 and a
>>>> spectrum analyzer, I actually demodulated the signal so you can be sure
>>>> that the values are quite accurate.
>>>> However the weird thing is that the mote did not rise to 0dBm, but only
>>>> to -4dBm. Sorry, I did not remember whether each column belongs to a
>>>> different mote. Also, note that setting the value to 0 it gives the maximum
>>>> power, but 1 stands for the least output power.
>>>>
>>>>   0 -4.1
>>>>  1 -51
>>>>  2 -46
>>>>  3 -29 -28.9  4 -22 -22.8  5 -22 -22.7  6 -22 -22.5  7 -19 -19.4  8
>>>> -16.5 -16.6  9 -16.5 -16.5  10 -16.5 -16.42  11 -15.5 -14.6  12 -13.8
>>>> -12.7  13 -13.7 -12.7  14 -13.7 -12.6  15 -12.4 -11.4  16 -11.1 -10  17
>>>> -10 -10  18 -10 -10  19 -9 -9  20 -8 -8  21 -8 -8  22 -8 -8  23 -7.2
>>>> -7.2  24 -6.5 -6.3  25 -6.5 -6.3  26 -6.3 -6.3  27 -5.7 -5.6  28 -5
>>>> -4.9  29 -5 -4.9  30 -5 -4.9  31 -4.4 -4.3
>>>> I hope this helps!
>>>> Cheers!
>>>> Sergio
>>>>
>>>> On Tue, Feb 21, 2012 at 6:10 AM, Xiaohui Liu <[email protected]> wrote:
>>>>
>>>>> Hi everyone,
>>>>>
>>>>> Does anyone know what the output powers are at each power level from 0
>>>>> to 31 for CC2420?
>>>>> The CC2420 datasheet only gives the output power for level 3, 7, 11,
>>>>> 15, 19, 23, 27 and 31. However, the output power for other levels like 2 
>>>>> or
>>>>> 12 are missing. I find some threads such as 
>>>>> 1<http://comments.gmane.org/gmane.os.tinyos.users/18536.>,
>>>>> 2<http://mail.millennium.berkeley.edu/pipermail/tinyos-help/2009-March/039014.html>
>>>>>  and
>>>>> 3<http://mail.millennium.berkeley.edu/pipermail/tinyos-help/2007-August/027345.html>,
>>>>> asking similar question, but no definitive answers based on measurements
>>>>> have been given. Please advise. Your help is truly appreciated.
>>>>>
>>>>> --
>>>>> -Xiaohui Liu
>>>>>
>>>>> _______________________________________________
>>>>> Tinyos-help mailing list
>>>>> [email protected]
>>>>>
>>>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>> -Xiaohui Liu
>>>
>>
>>
>
>
> --
> -Xiaohui Liu
>
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