Hello All,
I am currently working on my fifth RPi/Direwolf
APRS installation, and have ran into an issue
which has me stumped and hoping someone in the
group has an answer for, or at least,?can give me
a kick in the right direction.
First of all, some background:
The latest APRS station will primarily be used to
send back weather & telemetry on the vitals of
one of our local clubs VHF voice repeaters. The
repeater is solar powered and located in an
EXTREMELY remote mountain in the far north of
Canada, thus, during winter months,?(the shortest
days of the year in late December, the site gets
slightly more than 7 hours of sunlight a day), so
the power budget is VERY tight (not to mention the
financial budget our clubs 'Minister of
Finance':-)) At the same time temperatures
regularly drop at the site to -40 C (yes, that's
also -40 F for you folks south of the border),
which also drastically reduces battery capacity!
(Don't think the battery folks ever tested their
battery CCA's at our temperatures :-)). Operating
the RPi at these temperatures doesn't seem to be
an issue. We have one station that has seen these
temperatures on several occasions and is still
humming away. Moisture on the other hand is a
different story... Elmer Tip from years
of?experience in this environment: If you expect
extremely low temps, seal up & insulate your
electronics,?but before you do,?toss in?a few
Silica Gel packs to suck up the moisture?and
prevent frost forming on the electronics &
shorting it out.
I have already taken care of all the usual paths
of power conservation (right down to turning off
the LED on the Pi Zero to save that extra 5 mA),
but had another idea that would help conserve more
power at the most crucial times, but I'm not quite
sure how to tackle it.
One of the previous APRS stations I built was
a mobile with GPS module using the
SMARTBEACON/TBEACON. Worked great but got me
thinking,?"Would it be possible to do the same
type of ?Tx interval variations using the
CBEACON?"
For Example: With GPS SMARTBEACON the Tx interval
can be varied based on the speed travelling
(faster...more packets, slower...less
packets).?Might it also be possible to?send a
CBEACON in the same manner, ie. based on
temperature readings taken from a temp sensor on
the batteries? (Higher temperature...more packets,
lower temperature...less packets).?Guess you could
call it a SMARTCBEACON?
I've read through the Direwolf manual,
scanned the group and searched for any similar
solutions, but nothing?showing up.
Has anyone out there done anything similar or
have any thoughts on how it may be done? Any help,
suggestions would be most appreciated!
73,
DE VO2GO
Glen
