[TangerineSDR] Notes from PSWS / TangerineSDR of 12-07-2020

[Tom McDermott]

Notes from PSWS / TangerineSDR call of 12-07-2020

1. PI-uptime UPS 2.0 being used for power protection of Raspberry-Pi and
Magnetometer by several folks: https://alchemy-power.com/pi-uptime-ups-2-0/
It can use 18650 size Li-FePO4 or Li-Ion/Li-Polymer battery – jumper
selectable. (Note: The optimum Li-Ion battery temperature range during
charging is quite narrow, between 10°C and 30°C with problems at low
temperature (< 0C ), LiFePo3 has a lower charge temperature capability).
$57.99 on Amazon.com, $55.99 on tindie. Other battery types can also be
used. Board holds two 18650 batteries.

2. Discussion on whether the magnetometer should be aligned to magnetic
north or true north - pros and cons to each approach. The absolute accuracy
of the X, Y, and Z axis does not need to be extremely high because we are
looking for the delta of the 3-dimensional magnetic field vector against
the initial installation vector (which we do not want to change over time).
Additionally, citizen science groups may not be able to accurately orient
the device, so normalization of the as-installed configuration is desirable.

Nathaniel showed a document (IAGA) providing recommendations on how
magnetometers should be installed / aligned. It also provides math for
translating coordinate systems.  Document is at:
http://www.iaga-aiga.org/data/uploads/pdf/guides/iaga-guide-observatories.pdf

(The document says that either magnetic north or true north are acceptable
orientation alignment reference frames.)

Dave Witten requested a starting decision on what TengerineSDR should do so
he can continue writing the instrument software.


-- Tom, N5EG
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/tangerinesdr_lists.tapr.org/attachments/20201207/456f761a/attachment.html>