[TangerineSDR] Mag update?

[David G. McGaw]

Interesting, this, as it says on the RM3100 webpage "Measurements are 
stable over temperature and inherently free of offset drift" and a 
temperature coefficient is not even mentioned in the specs.

David N1HAC


On 7/31/20 11:44 AM, Julius Madey via TangerineSDR wrote:
> One more thought.  I've asked PNI for information both on temperature 
> and supply voltage sensitivity, the only two variables I could think 
> of besides the need to minimize local B fields due to currents in 
> circuit board traces, nearby wiring, etc.
>
> I did not find data on the temperature stability of the 3.3 volt 
> regulator Dave's JJ board  is using but the regulator I used with the 
> original adapter board Dave sent me has about 5 millivolts of change 
> out of 3.3 volts between 25 and 50 C and Dave's is probably similar.  
> That doesn't seem like enough change to produce the observed 
> variations but that information was given to PNI as well.
>
>
> On 7/31/2020 10:26 AM, David Witten wrote:
>> Hyomin,
>>
>> I'm not certain what the next step should be.  Julius is hoping for 
>> further response from PNI on this subject.
>>
>> If temperature compensation does account for the differences in 
>> observed response I would think that the important thing to  do may 
>> be to find a way to calibrate out the discrepancy.  Then we can look 
>> at insulation to further minimize the effect.
>> Calibration will hopefully give us more meaningful values to begin with.
>> Insulation will dampen the effect of those behaviors over short 
>> timespans.
>>
>> Fortunately, neither requires changes in the basic circuit, just 
>> adjustments to the data collection and device packaging.
>>
>> Dave
>>
>> On Fri, Jul 31, 2020 at 9:10 AM Kim, Hyomin <hmkim at njit.edu 
>> <mailto:hmkim at njit.edu>> wrote:
>>
>>     Hi Dave
>>     Sorry that I've been out of the loop for a while as I was
>>     completely caught up with something else. May I ask you what the
>>     current status is?
>>
>>     I can visit Jenny Jump if there is something that I can do. At
>>     this moment, I cannot think of anything that can be fixed from my
>>     end.
>>
>>     If the temperature compensation is the issue, I could install
>>     insulations around the sensor.
>>
>>     Hyomin
>>
>>
>>
>>     NJIT logo
>>     <https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.njit.edu%2F&data=02%7C01%7CDavid.G.McGaw%40dartmouth.edu%7C4a7b93ba3ecd455d4e0f08d83568b144%7C995b093648d640e5a31ebf689ec9446f%7C0%7C0%7C637318071068004568&sdata=O09d%2FBt6N3Iq%2FUVQ5KdQz6V0Km3YIN%2BucnCkc1JQC8E%3D&reserved=0>
>>     	*Hyomin Kim*
>>     Assistant Professor
>>     Physics
>>     Center for Solar-Terrestrial Research
>>     Institute for Space Weather Sciences
>>     hmkim at njit.edu <mailto:hmkim at njit.edu> • (973) 596-5704
>>     https://web.njit.edu/~hmkim/
>>     <https://nam12.safelinks.protection.outlook.com/?url=https:%2F%2Fweb.njit.edu%2F~hmkim%2F&data=02%7C01%7CDavid.G.McGaw%40dartmouth.edu%7C4a7b93ba3ecd455d4e0f08d83568b144%7C995b093648d640e5a31ebf689ec9446f%7C0%7C0%7C637318071068004568&sdata=W4LqWL2HfX4hkY0cMhqWDsY%2FlWS9nz1bpjcEZ9%2FbSNE%3D&reserved=0>
>>     104 Tiernan Hall, 161 Warren Street, Newark, NJ 07102
>>
>
>

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