Tag Archives: WebSDR

Aug 13 2015

SUWS WebSDR supports Meteor Scatter enthusiasts

Meteor pings received on SUWS WebSDR

Meteor pings received on SUWS WebSDR

The SUWS WebSDR, a popular resource for the Amateur Satellite and 434 MHz High Altitude Balloon communities, has recently been upgraded to support VLF and 49.990 MHz for Meteor Scatter observations.

The SUWS team hope that these new bands will further enhance the capabilities of the WEB SDR, which already covers a large proportion of the 2m, 70cm and 3cm Amateur bands.

The bands were added in order to try and replicate some of the work already undertaken by Dr David Morgan 2W0CXV and to make the SDR available as an on-line resource for others who are interested in observing such phenomena.

https://amsat-uk.org/2015/06/09/the-generation-of-vlf-emissions-by-meteors/

Antenna's at SUWS WebSDR site in Farnham

Antenna’s at SUWS WebSDR site in Farnham

Performance on the VLF bands is now quite good, but it still suffers slightly from some electrical noise from other equipment in the site and Sferic noise (Lightning discharges) from about 4 kHz upwards.

50 MHz is currently operating on a temporary antenna, but it is possible to hear the local beacons and repeaters, plus more distant Amateur stations during Sporadic E openings. So it is a good indicator of band conditions, but is probably not quite sensitive enough at the moment to allow detection of some of the weaker meteor pings emanating from the BRAMS CW radar on 49.97 MHz and IEPR CW radar on 49.99 MHz

However 143 MHz is working well and Pings from Graves on 143.05 MHz can be heard quite frequently.

Here is an example of how the WEB SDR can be used to detect meteors.

It is possible by looping a PC sound card input and output whilst running a web browser, to use Spectrum Lab to display a waterfall of the audio from the PC. Then by opening multiple instances of the WEB SDR in the browser, selecting USB and setting each SDR instance to a slightly different centre frequency and adjusting the filter pass-bands. It is possible to concurrently capture plots from VLF signals, IEPR, BRAMS and GRAVES and display them side by side on one screen (see attached). Because the same PC, Browser and internet connection is being used for all the signals, the plots should be almost time synchronous.

The SUWS team hope that these new enhancements will be enjoyed by their users, and expect that further improvements will continue to be made over the coming months.

Use the SUWS WebSDR at http://websdr.suws.org.uk/

Radio Astronomy Group Meteor Scatter Workshop takes place in Northampton on October 31
https://amsat-uk.org/2015/08/11/rag-meteor-scatter-workshop/

Getting started in Amateur Radio Meteor Scatter (MS)
http://www.geekshed.co.uk/getting-started-in-meteor-scatter-ms/

AMSAT-UK https://amsat-uk.org/
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AMSAT-UK publishes a newsletter, OSCAR News, which is full of Amateur Satellite information. A sample issue of OSCAR News can be downloaded here.
Join AMSAT-UK via the online shop at http://shop.amsat.org.uk/

What is Amateur Radio ? http://www.essexham.co.uk/what-is-amateur-radio

Feb 24 2015

Space Station SSTV and Packet Radio via SUWS WebSDR

ISS SSTV and Packet Radio signals on the SUWS WebSDR

ISS SSTV and Packet Radio signals on the SUWS WebSDR

Martin Ehrenfried G8JNJ reports excellent SSTV and Packet Radio signals from the International Space Station (ISS) using the online SUWS WebSDR.

144 MHz prototype helix antenna

144 MHz prototype helix antenna

The omni-direction helix antennas at the WebSDR were designed with high elevation satellites in mind. Conventional antennas concentrate the radiation pattern towards the horizon resulting in weaker signals when a satellite is above 15 degrees elevation. Comparisons with other WebSDRs show the SUWS antennas provide a 6 to 10dB better signal to noise ratio on similar passes.

Martin says: “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.”

You can use the free online SUWS Web Software Defined Radio from your PC or Laptop to receive the ISS and the many amateur radio satellites transmitting in the 144-146 MHz or 435-438 MHz bands. It also provides reception of High Altitude Balloons in the 434 MHz band and coverage of the microwave 10368-10370 MHz band.

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/

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

Brazilian radio amateur uses SUWS WebSDR to receive ISS SSTV
https://amsat-uk.org/2014/09/06/iss-sstv-on-suws-websdr/

ISS SSTV image 9/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR on Dec 18, 2014

ISS SSTV image 9/12 received by Martin Ehrenfried G8JNJ using the SUWS WebSDR on Dec 18, 2014

Aug 15 2014

SUWS VHF/UHF/Microwave WebSDR moves to new site

Antenna's at SUWS WebSDR site in Farnham

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

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/

Mar 19 2014

SUWS WebSDR for VHF/UHF/Microwave

23cm_WebSDR_Antenna_up_mastThe SUWS WebSDR, a VHF/UHF/Microwave online radio, now has improved antennas for reception of amateur radio satellites and High Altitude Balloons (HAB).

Noel G8GTZ has posted an update on the Southampton University Wireless Society (SUWS) web based software defined radio covering the 144, 432, 1290 and 10368 MHz amateur radio bands. On the UK Microwave Yahoo Group he writes:

A quick update on the status of the SUWS microwave SDR http://websdr.suws.org.uk/

10 GHz – the Octagon PLL LNB based system is working well and now has the correct frequency labels on the scale (rather than the RTL dongle tuning range).  The Octagon does drift up to 30 KHz high with temperature which is not bad considering it is unmodified and mounted on the mast,  and you can get an accurate frequency calibration from GB3SEE which is visible at all times on 10368.850.  We have seen some very interesting propagation effects (both RS and tropo) with GB3CCX and GB3LEX was audible last week during the lift.

1.3 GHz – the SPF pre-amp is now mounted at masthead.  There is some small frequency drift from the RTL dongle but GB3FN is very loud at all times and GB3MHL / GB3DUN are now audible with the any improvement in condx or aircraft scatter (Heathrow lies directly on the path to MHL).

144  MHz and 432 MHz – We are trying a new type of mixed mode helix antennae on both bands to improve satellite and HAB reception and it seems to be working very well – see
http://g8jnj.webs.com/currentprojects.htm

Listen to the SUWS WebSDR at http://websdr.suws.org.uk/

WebSDR for 434 and 1296 MHz https://amsat-uk.org/2013/12/28/websdr-for-434-and-1296-mhz/

UK Microwave Yahoo Group http://groups.yahoo.com/group/ukmicrowaves