Bill of Materials (BOM)
The following items will be needed in order to complete the v3 build. They are split into the Azimuth and elevation sections
Azimuth Need link to spreadsheet
Elevation Need link to spreadsheet
Build Sequence
For the v3 build sequence go here[1]
Sources for parts
3d Printing at a Fab Lab- If you don't have your own 3d printer then a local Fab Lab may be able to do it for you. Fab Labs are places that have invested in the machinery and you can take the designs to them. Generally they need .stl files to import into the software that runs the machines but this should be discussed with the Fab Lab. You then pay for the colume of material or tme or a combination of the two for each of the parts [2]
T Slot - If you don't want to cut the pieces yourself then here is a UK supplier[3] Hidden corner connectors - AliExpress gave the cheapest supplier
Stepper Motors - eBay
Belts - eBay
Fixings - eBay
Antenna Hardware The yagi antenna is suited to the novice builder but there are many types. Each satellite has an uplink and a downlink so it is necessary to have an antenna that will work on the downlink side for receiving and one for the uplink if you are transmitting to the satellite (Transmitting requires a licence - an amateur radio licence normally suffices fr most countries). Antennas have a gain associated with them that is related to the number of elements. Simply the greater the number of elements the greate the gain, however the more directional they become and the greater accuracy is needed. So a trade off between gain and beam width is required. Nominally a 3 element beam for 145Mhz (2m band) and a 7 element beam for 432MHz (70cms band) will suffice for most applications. Some satellites need a different type of antenna that has circular polarisation and these are helical to look at. The satNOGS helical design should be followed.
Receiver
The RTL-SDR dongle used for the reciver is a broad band software defined receiver (SDR) that uses a common IC for the receiver and simple filtering. Its intended use is for TV, FM and DVB reception. It can be hacked, using the right drivers to be a very capable and cheap receiver. Fot further information see here[4]
