Autonomous Satellite Tracker

This page refers to my Autonomous Satellite Tracker article in the March/April 2016 QEX. All updates will be posted here.

Supporting Material:



  • Version 2016061704 fixes a problem that prevented entering values in Firefox and Android.
  • Version 2016073023 fixes a problem that prevented downloading elements from AMSAT or
    Celestrak in Firefox and Android.
  • Version 2016082822 fixes a problem with refraction near the horizon.
  • I've added a closeup photo of the way I connected the tracker to a tripod. I bought a
    small tripod and pulled the center post up through a channel then clamped to it. The
    tripod post is 5/8" diameter. ServoCity part numbers: 3x 585548, 1x 585443, 1x 545360
    and 2x 585596.
  • Notes from a builder, WA7DLG.
  • Gregg, W7GRM, reports the HS-7950TH servo for the SPT400 platform is strong enough even for the Arrow antenna.

Update 2018 July 29: The Tracker is now available using the ESP8266 processor, the same one used in my HamClock. This eliminates the need for the Arduino, ethernet shield and the TP-Link. The wiring diagram and interior view are now just this:

The wiring for the Servo controller, 9 DOF Sensor and tilt and pan servos is the same as in my original design. Note the change from 5 to 3.3 V supply for which the Huzzah EN is grounded. If you use a 5 V supply then leave EN disconnected.

Update 2020 Jun 16: Changes:

The new sketch is here. Set up the Arduino IDE for the Adafruit ESP8266 Huzzah exactly the same as for my HamClock project. You also need the following libraries: TinyGPS, BNO055, Sensor, Servo and of course the ESP Arduino port.

Other helpful links: Arduino IDE, Arduino libraries and ESP Huzzah, version 2.4.0.

The Tracker functions exactly the same way as described in the original article except how it connects to the network:

Let me know what you think!

73, Elwood Downey , WBØOEW