Antenna’s at SUWS WebSDR site in Farnham

The Southampton University Wireless Society SUWS VHF/UHF/Microwave WebSDR has now moved to its new site in Farnham.

You can use the free online SUWS Web Software Defined Radio (WebSDR) from your PC or Laptop to receive the International Space Station (ISS) and the many amateur radio satellites transmitting in the 144-146 MHz or 435-438 MHz bands.

The WebSDR also provides reception of High Altitude Balloons in the 434 MHz band and coverage of the microwave 10368-10370 MHz band.

144 MHz prototype helix antenna

Martin Ehrenfried G8JNJ has equipped the SUWS WebSDR with omni-direction helix antennas for both 144-146 MHz and 432-438 MHz which have proved effective for both high altitude balloon and satellite reception.

The SUWS WebSDR is located at Farnham not far from London, 51.3 N 1.15 W, listen to it at http://websdr.suws.org.uk/

Martin says this about the special satellite antennas “I had been experimenting with single turn ‘twisted halo’ design, and decided to try stacking them to see if I could achieve more gain. Modelling suggested that a stretched 3 turn helix with a helix circumference of approx 1/2 wave length and an overall length of 1/2 wave at 70cm, and fed with a gamma match at the centre would offer reasonable gain, an omni-directional pattern and mixed polarisation.”

Full details of the antennas are available at
http://g8jnj.webs.com/currentprojects.htm

A presentation by Phil Crump M0DNY on the SUWS WebSDR will be streamed live to the web from the UKHAS Conference on Saturday, August 16, see https://amsat-uk.org/2014/08/14/ukhas-2014-conference-live-video-stream/