satellites are fascinating but costly
and therefore
only available for governments the
military and recently
also billionaires undiscovered for most
there is another trend universities and
small companies can build
and launch satellites because most of
these satellites use
open transmission standards everybody
can listen to them
today we will look at a hobby project
which enables us to do so
in addition the project uses some
innovative concepts
where we can learn a lot for our
projects
and it shows what the maker community
can reach
if we want gritsy youtubers here is the
guy with the swiss accent
with a new episode and fresh ideas
around sensors
and microcontrollers remember if you
subscribe
you will always sit in the first row
in video number 301 we shared the
excitement
when we saw 16 year old julian launching
his first
lora satellite fossa sat 1.
unfortunately it never was able to
unfold its antenna
and solar panels so most of us
never heard a signal will we be more
successful this time
a lot happened since then so in this
video we will
get an update on the launched lora
satellites
as well as on the planned ones we will
build a 20
satellite ground station and connect it
to a global network of ground stations
we will learn about the very innovative
tiny gs
project the project team's combination
of telegram
tasmatizer ota node red
and more can be food for thought also
for our projects
in video number 305 we accompanied the
first commercial lora satellite
launched by the small lacuna startup
company
in the meantime they operate three
satellites
and i still have a sensor in my garden
that regularly transmits data
through these satellites to ttn
here you see the successful
transmissions of the last 30 days
most of the days more than one satellite
passes my home
and receives my data on the 868
megahertz ism band
what happened to julian's company
fosasat
and the project we started back then to
build a ground station
to receive the packets fosazat built
new satellites which are planned to be
launched during the next few days
the launcher will be firefly but the
chance
these satellites will be deployed is not
100
because it seems to be their first
launch
and there is no news about when the
start really will take place
fortunately in summer fosazat plans to
launch more satellites using a space x
rocket in parallel many more satellite
projects were started by universities
some of them have already launched and
more are planned during this year
if corona permits and the ground
stations to track the satellites
we built back then it was extended and
renamed into
tiny gs because now it can track
all sorts of satellites very valuable
for the satellite owners
because they get a global coverage let's
start with the different satellite
projects
you find a comprehensive collection on
the tiny gs
home page all projects have different
purposes
use different frequencies and
modulations but
a closer look reveals a few patterns
all are leo or low earth orbit
satellites
because their tracks are only a few
hundred kilometers away
from the surface they move extremely
fast across our homes
and are only visible for minutes on the
other hand
they appear quite often in contrary to
geostationary satellites
which orbit 36 000 kilometers above the
equator
like that geostationary satellites seem
not to
move and we can point our satellite
dishes
in one direction only in my series about
the q0100
i built a ground station for such a
satellite
and talked to another swiss amateur
radio operator in antarctica
later you will see my 120 centimeter
dish
on the roof most of these new cubesats
use
lora modulation and only a few
traditional frequency shift keying or
fsk modulation we will later see why
most of them use the 430 to 440
megahertz amateur radio band
only the american ones use the 915
megahertz ism band
one satellite will use 137 megahertz and
one
the 2.4 gigahertz wi-fi band
most of them are already launched or
will be launched in the next month
a perfect time to start with building
our new ground station
to observe what happens because they
transmit on frequencies
we easily contract with our standard
lora modules
such a ground station costs around 20
dollars
i will use this ttco lora module which
uses wi-fi
to transfer the received messages to the
internet
there are other similar ports available
and we will later see
how the tiny gs project deals with the
different pin assignments of these
sports
but why do most of the projects use lora
modulation
the link budget of lora is very high
this means that we can receive signals
from
low power satellites using standard
antennas
if you want to know more about the link
budget you can watch video number 112.
as said before the satellites change
their relative
speed while passing our location like
police cars
passing by
they create a doppler effect that
changes the frequency we receive
standard modulations do not like such
frequency changes and stop working
if we do not regularly adjust our
receivers
laura uses so-called chirps which vary
in frequency
and therefore is much less susceptible
to frequency changes
enough talked let's now build our ground
station
we only need a few things an esp32
board with a lora module for the
frequency range we want to listen to
remember that you have to choose between
the 433
868 and the 915 megahertz version
i use a 433 megahertz module
because most of the satellites transmit
in this range
the tiny gs team is also happy if we
build 915 megahertz devices
because up till now they are rare
next we need software that is capable to
decoding the received packages
fortunately this is provided by the tiny
gs project
then we need an antenna i built a ground
plane as shown in video number
369 as you see it has decent performance
on the whole band
last but not least we need power and the
case
i use such a small 5 volt power supply
and my standard
waste pipe with a 3d printed holder for
the board
and the power supply inserted from the
bottom
the whole device is powered by mains and
automatically connects to wifi
in the video description you find a link
to the needed software
you can compile your version but the
easiest way is to download the project's
firmware uploader
just select the right com port and hit
upload
done in my opinion this way of software
distribution
invented by the tasmatizer project is
the way to go for many future projects
particularly for esp32 projects where
all
subsequent updates can be done using
over the air updates
if you want to use this method for your
project
i suggest studying the changes tiny gs
had to make to tasmatizer
these are probably the changes you have
to make to create an
upload for your project now we can
configure our particular port
the display shows that we have as usual
to connect to my tiny gs and call
192 168 4 1
to get the configuration screen and as
usual we have to enter a name
a password the wi-fi credentials and our
station's position
there is no need to enter the exact
position if you do not want to show
other people
where you live this position is used to
determine
which satellite is visible above your
ground station
the next step also can be used as a
blueprint for other projects
the mqtt credentials are created using
the telegram app
in telegram you have to search for tiny
personal bot
it offers four options the first option
creates your mqtt credentials
the last one creates a private link to
your user console
by the way do you want to know how they
do this telegram integration
they use node-red it has all the
capabilities to work with telegram
i use it in a much less sophisticated
way for my projects
as a dead man's pedal for my sensors
because i expect a message every few
minutes
from my awning remote control something
went haywire
if no message arrives for 5 minutes or
300 seconds
and this note sends a message to my
telegram bot
simple and efficient if you want to know
how to integrate telegram into node-red
you can watch video number 270.
next you have to select the board they
implemented some sort of autoconfig
where the sketch tries to determine
which board you use
also a cool idea that could be used for
many other projects
particularly with the many slightly
different ttgo boards
it reduces user intervention and
frustration
they include all supported boards with
their respective pins
and addresses then the sketch has to
check all possible pins
and addresses to see if it gets an
answer
if not it tries the next configuration
we can also use this idea to improve
how we design our projects especially if
we want to make them available for many
users
before you hit apply and reset the part
please check the other tick marks of the
config
only select enable tx if you are a
licensed ham and automatic firmware
update
if you trust the project after a few
seconds
you get a telegram message that your new
ground station is connected to the
network
and you see its ip address on the oled
if you connect to this address you see
this menu
please log in with admin and the
password you choose before
the dashboard shows that your station is
connected to the tiny gs
network and is already waiting for the
next satellite crossing your
location but how does this small device
know which satellite will be next
people who watched video number 302 know
that there is software available to
predict satellite tracks
here you see g predict where i chose the
two currently active lora satellites
norbi and sdsat i'm currently outside of
their footprints
and not able to receive them here you
see an example of an
sd sat pass across my antenna
if you watch your receiver's dashboard
you will discover a change in receiving
frequency and modulation parameters
from time to time because i selected
allow automatic tuning
tiny gs gets this information from the
project to prepare for the next
satellite pass
you do not have to care here you also
will see
when your station received packets from
space
if you go to tinygs.com you should find
your station as well as all tracked
satellites
depicted on a map test satellite ism
433.3 by the way is not an active
satellite
it will be used by a second lora board
and
emulate this satellite to test our
receiver before we deploy it
on the roof this step is optional
if you trust your work you can deploy
your receiver without further testing
and wait till it receives satellite data
but because i'm an engineer i treat
untested systems like defective systems
this is why i flash a second board with
the same software
the same mqtt credentials but with a
different
name and tick enable tx
this part now acts as my test satellite
legally transmitting on 433.3 megahertz
in the ism band
we go now to our user console
you got the address from your tiny gs
personal bot
here we see our boards and also that
messages
they received we select the test
satellite for both
boards
and send a message by pressing p in the
user console
of the test satellite if everything
worked
you get a success message in telegram
now we know that our receiver is working
do not forget to select automatic tuning
for your
receiver if you want to receive
different satellites
and deploying on the outside where it
can see
the sky the test board is no more needed
and can be used for another project
this is my finished station to keep my
antenna apart from the tube
i use a semi-rigid coax cable
it can be bent to the position you want
and it stays there
very convenient for such applications
let's put it on the roof
you see it gets more and more crowded
here is the lora gateway
this is the weather balloon tracker of
video number 360.
this is the q0100 ground station
this one is for 2 meters and 70
centimeters ham radio
and this long wire for 3.6
to 30 megahertz it is suitable for
direct contacts around
the world so my new satellite tracker is
in good company
and it will never feel lonely maybe even
a little beaten up
if this antenna transmits 100 watts
nearby
and did i already receive satellite
messages
yes of course norbi works well and i
regularly get messages when it passes
overhead
i see the messages in my user console as
well as
in the tiny gs telemetry channel
by the way here you can see how far lora
transmissions can travel
if there is a line of sight of course
i hope somebody will set up additional
ground stations
in areas like south africa or the us
heartlands also asia is not covered
enough
and what should we remember satellite
technology became affordable
that even makers can participate the
tiny gs project is very innovative
combining cloud services with standard
boards
they were able to create a global
tracking network for all sorts of
satellites
automated firmware uploaders should be
considered as a standard for software
distribution
provisioning of credentials and other
secret data
using telegram bots is a cool idea
it uses readily available services for
our purpose
i put such hacks in the same category as
ikea hacks this network is essential for
future experimental satellites
because they can rely on a network of
ground stations
with more notes than nasa and spacex
together
all made by makers i like it
as always you find the relevant links in
the description
i hope this video was useful or at least
interesting for you
if true please consider supporting the
channel to secure its future existence
thank you bye