Ground Station

We're building a ground station at London Hackspace: 51.53ºN, 0.06ºW.

Radio Overview

HackSat One broadcasts on 437.240 MHz (70 cm band), sharing its frequency with the other KickSat sprites using CDMA. The broadcast power is 10 mW. More information is also available from the IARU Sat Coordinator. HackSat One's usable bandwidth is approximately 6 bits per second (45 bytes/minute), it varies somewhat due to random nature of the asynchronous CDMA used.

Nature has a good graph of satellite bandwidth (admittedly for Earth-Jupiter distance) that shows how limited many satellites have been. See Lasers boost space communications for the related news story.

Mast & Antenna

With an orbital inclination of 51.6º, it's possible for HackSat to pass directly overhead in London, but most of the transits will be in the south. Unfortunately, the yard at London Hackspace faces north. Thankfully, we have recently acquired a 30m mast trailer mast that will allow us to mount an antenna above the local buildings.

30m Mast Trailer: for mounting the antenna. See Hackspace wiki for specs.

We have a handheld Arrow II antenna for testing. For the actual mission the intention is to have a steerable antenna on the top of the mast trailer. More details to follow.

Receiving & Decoding

To decode the signal we're using a FUNcube Dongle Pro+ and GNU Radio. More details to follow.

Sprite Decoding: first successful decode of a signal from the dev board using GNU Radio.

Decal by Nick Cramp.