[aprssig] Autonomous EMCOMM Telemetry

[John Langner WB2OSZ]

After you have the proper sensors to gather data, you need a way to encode
the information and send it as telemetry.

Here is an APRS Telemetry Toolkit that you might consider.  It includes an
example of connecting an A/D converter to a Raspberry Pi and transmitting
the voltage measured.

https://github.com/wb2osz/direwolf/raw/master/doc/APRS-Telemetry-Toolkit.pdf