a day ago •
It was time for us to test out the designs for our PCB that would take care of the motor control.
a true hackerspace fashion instead of ordering the PCB we decided to
built the capacity to produce our own (much needed moving forward). We
could not settle for a simple single-side capability with no solder
mask, so we shot for a typical side-project extravaganza :) What we
ended up with was a double side capable UV exposer controlled for timing
and after many tests the expertise to apply solder mask for uber cool
finishing for our diy PCBs.
to SatNOGS specific PCBs the design was slightly changed from v1. We
changed the capacitor, rerouted for optimal setup the board and thanks
to [n0p] comments we added breakouts for unused Arduino pins (you never
know what you will need!).
Production went smoothly and the PCB test showed that everything was in place correctly!
the finished v1.1 motor control PCB ready we thought that we could tidy
up our power circuits too. That called for a PSU PCB tailored to our
needs. Agis, our team electronics expert, quickly designed a PSU PCB
based around a Voltage Regulator capable of having an input of 12V DC
and an output of again 12V DC plus 5V DC stable through USB Type A too.
Production once again was smooth and we ended up with our PSU PCB. Pics below are from a slightly modified version with a cap (both designs can be found in our repo).
Detailed designs and Gerber files can be found in our Github repo
steps for our electronics will be to focus on the auto-homing circuits
(using the handy breakouts!). A separate log on that will follow!
3 days ago •
outlined in project description and previous logs, a central part of
our projects is what we call "SatNOGS Network". SatNOGS Network is a web
application running on a server that takes care of discovery of ground
stations, registering of users, scheduling and job-detailing of
observation as well as data collection and analysis once an observation
3 straight weeks of python/django hacking and almost 100 commits, we
are proud to have a working prototype of the SatNOGS Network.
model of the application is now polished and able to handle all basic
operations for Stations, Users, Observations, Satellites, Transponders,
Antennas and Data.
in line in terms of functionality implementation is the ability to plan
observations based on user provided info (satellite, transponder etc)
using SGP4 in python, and also a detailed view of Observation (with data and timeline).
The main page features a map with all ground stations, details about a featured ground station and latest completed and scheduled observations.
The code can be found (follow and contribute too!) here: https://github.com/satnogs/satnogs-network
A live development version of the website with demo data [WARNING ;)] can be found here: https://dev.satnogs.org/
a month ago •
is focused on TX operations for Low Earth Orbit (LEO) satellites. Most
satellites in those orbits transmit signals in relatively low power
(compared to GSO satellites). 100mW to 2W is a typical range for LEO.
Given that power output and our RX assembly (yagi + dvb dongle for
reception) a Low Noise Amplifier can really improve our RX capabilities.
decided that LNA would be an integral part of our RX assembly early on,
but we could not easily find something that would meet our requirements
(bands, noise figure, cost, size etc). After browsing and researching a
lot of different options out there, we stumbled upon LNA4ALL.
 is a great project by 9A4QV. The amplifier is built around
Mini-Circuits PSA4-5043+ E-PHEMT Ultra Low noise MMIC amplifier
operating from 50 MHz to 4 GHz. Small SOT-343 package combine low noise
and high IP3 performance with internal match to 50 ohms. With 20 Euros
as a pricetag, this was the LNA we were looking for.
are using our 5V output from the regulator we have inside SatNOGS as
VCC for the LNA (required a tiny bit of modification) and the LNA is
connected in line between our RX dongle and the antenna (using SMA
tests are showing great improvement in our reception (tested against a
variety of bands, encoding and satellites) making this LNA an
irreplaceable part of our project.
shielding and housing should be in place, so we designed  and 3d
printed quickly a housing for this LNA. Some grounded aluminum tape
makes up for a shield.
More tests will follow, and we are designing new antennas and evaluating their matching.