[TangerineSDR] longer cable test

[Julius Madey]

Currently have the RM3100 reporting nicely on 400 feet of Cat5Eshielded 
outdoor/direct burial cable; Cat5 is worst case; Cat6 will be better.

Still running 3.3 volts into the local end of the cable as in original 
testing with 120 foot run no voltage regulation on the remote.
Still using Dave's original test board with the temp sensor.
With a 220uF cap across incoming power on the remote end, I see about 
250mV drop during data transfer.
100KHz i2c bus SLC and SDA waveforms clean.
Will take additional data over the next couple of days and post. Then 
will move to 5 volt feed on the local end with 3.3V LDO reg on the 
remote for comparison.
Cable delay <500ns.
Clearly haven't hit the distance limit yet.
Jules - K2KGJ


On 5/20/2020 12:53 PM, David Witten wrote:
> All 'magnetometerists':
>
> I am actively updating the software on Github ( 
> https://github.com/wittend/rm3100-runMag ). I appreciate all of the 
> input I am getting.  Both Julius Madey and Dave Larsen have been 
> especially helpful. Check for updates often (if you have cloned the 
> repository, just use git pull from your projects base folder).
>
> The time is coming where I am going to have to ask folks to submit bug 
> fix / feature requests using the 'Issues Tracking' feature on the 
> repository ( https://github.com/wittend/rm3100-runMag/issues ) so that 
> I can avoid losing them in my email and prioritise them rationally.
>
> My latest commit updates the presentation of the output somewhat.  
> Important changes include more understandable messages regarding 
> missing sensors, presenting some of the values with more decimal 
> places, and more useful presentation of values entered on the command 
> line using the -P option.
>
> Other work continues on several fronts.  Most important (to me) at the 
> moment is synchronizing the Cycle Count (CC) values with the Gain used 
> for computing output.  Also important is constraining the CC input to 
> values that the sensor will accept.  Some other value inputs need to 
> be sanity checked.
>
> Please test this and give me your input and frustrations. Now is a 
> good time for me to work on this.
>
> Dave Witten, KD0EAG
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/tangerinesdr_lists.tapr.org/attachments/20200522/1f77e87d/attachment.html>