Hello to all from IZ5RZR Massimiliano

Being passionate about satellite communications, given the high cost of existing rotors that well over a thousand euro / dollar, as well as the high cost of dedicated antennas, I decided to build me a rotor, starting from scratch, and a series of antennas that I allow you to do this activity with an acceptable expense and satisfactory results.

Thanks to the amazing work done by the Greek Team SATNOGS and IK5XWA Francesco, as developed and made available online in recent months I decided to build a rotor azimuth antennas - elevation for tracking of all types of satellite, polar or geostationary. The rotor is equipped with a control box can be controlled manually via the three keys (DIRECTION UP - DOWN and CHANGE ENGINE), or via software by pc with Yaesu protocol GS-232, and then interfaced to Orbitron program to other dedicated software, equipped with such protocol.

The electronics and the software SATNOGS Team, provides for the control of the rotor via the microcontroller "ARDUINO MICRO PRO" placed inside the same box and the rotor involves the construction of a specific PCB (which however I am 'made), a further pcb for the system power, which is fed to 24:05 volts, and use a TP-LINK router modified in firmware (openwrt) for the remote control and the connection with a SDR RTL2832U connected streaming via TCP- IP. In this case, however, the electronics being mounted near the antennas generates considerable interference on the radio and SDR systems apparatuses, therefore I opted for the production of a rotor with mechanical "SATNOGS", printed completely in PLA material, with my 3D printer "Anet A8 ", but using the electric circuit designed by IK5XWA, which uses a simple ARDUINO UNO programmed with the C ++ code given me by Francesco and suitably modified by me to work with the SATNOGS rotor. Electronic systems are inserted into a CONTROL BOX external to the rotor, shielded with toroids so as to reduce as much interference as possible. The circuit is realized with the following material:

• Arduino UNO;

• 2 stepper motor NEMA 17

• 2 drivers for stepper motor Pololu A4988;

• 3 buttons for pcb;

• 3 resistors 10k

• 2 100 uF capacitors to protect nema 17

• 1 digital voltmeter;

• 1 RS232-TTL converter USB to connect Arduino UNO with pc;

• doupont Cables breadboard

• 3 PVC 32 mm tubes

• 2 bearings for modeling

In this way I built a STATION OF TRACKING SATELLITE MOBILE that allows me, with the simple use of a PC and a power supply of 12 v (hence photovoltaic in my case), installed in a few minutes the station and enjoy myself receive weather satellites NOAA and METEOR, ISS, amateur radio, Inmarsat, etc. and combine them with each time dedicated antenna with a simple coupling / uncoupling system of the boom.

Here some phases of realization:


Stampa in 3D del Worm gear               assemblaggio dei componenti stampati e montaggio del Nema 17


Stampa in 3d del frontalino del control box personalizzato

 Stampa degli “antenna holder” per realizzare le yagi

Test del sistema satellitare con due antenne montate: antenna dual band VHF-UHF + antenna cross yagi dual band VHF Milsat + UHF in polarizzazione circolare destra “RHCP”

Antenna dual band 4 el. VHF + 5 el. UHF ultraleggera con boom in pvc da 25 mm e holder stampati in 3D e stili in ottone per saldatori

Wiring diagram reproduced by me on Fritzing and designed by Francesco IK5XWA modification capacitor 100uF as Pololu specifications to which you can add a voltmeter and possibly an I2C LCD display (for future implementation).

For more info, please email suggestions and improvements.’73 de IZ5RZR – http://www.caturegli.it