Tuesday, November 29, 2011

WWW-SDR - Multi-tuner

To demonstrate the ability to run multiple tuners at once, I configured the server to run 3 x tuners concurrently. The www view demonstrates this view, with multiple spectrum modes as well.  Each receiver can be controlled independently of the others - but combined in a single www view.

Ability to view multiple receivers via a single browser.

Saturday, November 26, 2011

2011 - SDR with CQWW DX CW

After many performance experiments (server vs. browser) the SDR processing still lives on the server.
I have uploaded about 7 mins of 96KHz sample data from the 2011 CQ WW DX CW contest.

Feel free to try it out here 

Please leave comments and feedback.  This is a work-in-progress project, and has served as a vehicle for DSP technique experimentation, while having fun with weak signal modes.

Monday, September 5, 2011

WWW-SDR : Multi-decode view.

The WWW-SDR now supports sdr rx functionality with tune/demod/filter.
This view above demonstrates the ability to run multiple independent radios in a single www browser.
In this example, both www-radios are connected to the same SDR server but running different waterfall modes

The multi-threaded server architecture supports multiple radios, each serving multiple www-clients.
Server-side capacity is mostly limited by network I/O & CPU.

Read more about the features and release notes here.

Sunday, August 21, 2011


Around 0630Z, 20m was open to Japan. Here you can see the clear trace from SSTV tx from JA2GZZ
on 14.233MHz.

SDR functionality is now almost complete. From the browser you can Tune, Filter & Demodulate

The SDR radio is now usable, via anywhere on the www.

73, Deon
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Sunday, March 27, 2011

Internet SDR - audio streaming

Project notes here:

Added audio streaming to the www client.  Also more UI features such as display pan/zoom
and controls for pause/muteof the data feeds - which will optimize the network bandwidth usage.

I'm now working on adding full SDR receive capability to the www client.
This will allow multi-vfo tuning of the radio from the client.

Feel free to connect as often as you like. The radio is mostly tuned to the high bands during daytime, and
40m at night time Pacific time.

Friday, March 18, 2011

Online SDR - Its alive.

The Online SDR project has been coming along nicely.

The results of a few late nights work appears to be working good so far.
The multi-digital decoding engine is also working fb.Now that the digital decoder is working, then next step is to implement a fully internet enabled SDR.

If you want to follow along, project notes can be found here: ReleaseNotes.

Here is a snapshot of the Online SDR (Single radio mode)

The SDR server and UI supports multi-radio capability.

Independent radios can be visible in a single view view.

Saturday, January 15, 2011

Jan Mayen 2011 - JX7VPA

You can follow the status of planning on dx-world.net.


Stan SQ8X is pleased to announce that today he has received an email from The Norwegian Post and Telecommunications Authority (NPT) granting ham radio license – and permission to transmit from Jan Mayen island.
JX7VPA will be a group callsign used during the DXpedition scheduled for July this year.
The timetable as follows:
  • July 2 – the team gathers in Reykjavik, Iceland.
  • July 4 – departing for Jan Mayen with a charter yacht, 2 days on the sea with a chance to sign as /mm.
  • July 6-14 – ON THE AIR.
  • July 14 – tearing the camp down, sailing back to Iceland.
  • July 16 – back in Iceland.
Due to polar summer season at Jan Mayen Island with broad daylight 24/7 the team will not operate on 160-80 meters – those bands will be totally dead at that time. DXpedition will focus on 30-6m and our main modes will be CW and RTTY/PSK, with some SSB if conditions will be good enough to operate as much as we wish to. The team will also check conditions on 40m band, but the band may also be not usable at that time of the year.
The team will have a professional TV crew onboard that will prepare a broadcast documentary about the project and the island. All details as updated operators’ list, QSL route, bandplan and such will be announced soon on a dedicated website http://janmayen2011.org (under construction).

Tuesday, January 11, 2011

2010 - ZS1D Piketberg Portable

Dec 17 - 20, 2010.

Our mountain top location for this trip is about 100 miles north of Cape Town.  1800ft elev.

The multi-band vertical is easy to setup and the station is on-air within minutes.  Antenna is based on a design from the ARRL handbook - multi-band design based on a bottom loaded design.

Scanning the 40m band results in a few local QSO's but nothing too exciting.  We easily establish contact with ZS stations about 1000 miles away.  During the afternoon, 20m opens up with some longer distance dx. 
We easily manage a few QSO's with Europe around 14h00Z.

Our Cabin under the clear Milky Way night sky.
During the late afternoon, 20m grayline allows an easy path to EU.  Soon after that the path switches to NA, with both 20m and 40m paths between 17h00Z - 20h00Z.

 706 with Vertical and the view from the shack

Roelof, ZS1XD taking a well-deserved break from all that dx...
 The field kitchen at the nearby camp site.
 View from the shack - looking east towards the reflection of sunset