Sunday, June 10, 2012

About This Project - redux

Recently, I started thinking that I'd better capture some of the history of the RBN before passage of time and an aging memory obscured it forever.  The About This Project section on the RBN website needed updating anyway, so I collected a few key dates from e-mails and Skype logs, and here it is.  I hope you enjoy it.

About This Project

The Reverse Beacon Network was borne out of an e-mail exchange in March of 2008 between PY1NB and N4ZR.  Felipe had been running a unique DXing web site,, for several years, while Pete had been working with VE3NEA, the author of the CW Skimmer software, since late 2007 to test, develop and refine it.  Felipe saw a way in which the basic framework of DXWatch could be adapted to display Skimmer spots at a central location as “reverse beacons”, spotting everything they heard.  Early in April, Felipe wrote the first Aggregator software, intended to receive spots from Skimmer’s Telnet server and transmit them to the web site for display.

The web site was initially the only way to view Skimmer spots. But as the controversy raged in the contesting community over whether unassisted single operators should be allowed to use this new technology, it occurred to the RBN operators that there might be an opportunity here to contribute Skimmer spots to the worldwide contest and DX community through a Telnet server using DX cluster software.  We had no clue how quickly this would change contesting.

It took a while, but in April 2010 the Telnet server debuted.  Almost immediately, it proved very popular, to the point where the server began to buckle under the load of being the only outlet for RBN spots  

At first, there was general consternation at the thought of Skimmer spots being integrated into the traditional DX cluster structure, for fear that their sheer volume would submerge the traditional spots people were used to.  Happily for the RBN, though, writers of cluster software soon recognized that they could accommodate the RBN spots by providing filters to segregate the Skimmer spots if desired.

Meanwhile, Nick, F5VIH/SV3SJ joined the RBN team.  His computer science background was a great asset, and in July 2010, he rolled out the Signal Analysis Tool, a graphical way to compare signals of multiple stations on multiple bands, as heard by a single Skimmer anywhere in the world. 
In September 2010, VE7CC and VE1DX began distributing RBN spots through their cluster servers.  Shortly thereafter, AR Cluster Version 6 was released in beta with similar provisions and an advanced filtering scheme. 

 In November, just in time for CQWWCW, Dave, KM3T joined the team.  He, Nick and Felipe worked hard to ensure that the RBN servers would not fail during the contest.  They succeeded, and the Telnet server delivered over 1.7 million spots without incident.  In March of 2011, a second Telnet server running ARC6 was added to the RBN’s facilities, spreading the load and allowing for distribution of Skimmer spots to ARC6 clusters worldwide.

In September 2011, Dick, W3OA joined the team and wrote the first Windows Aggregator.  The beta was a success, and in succeeding months he delivered increasingly sophisticated versions of the software, which is now in release 2.1.  In November 2011, the RBN handled 3.25 million spots during CQWW, an average of 18.9 spots per second, with no problems.

So far in 2012, the RBN’s servers have been handling the load nicely. The  ARRL DX contest, the Russian DX Contest, and WPXCW passed without incident.  In WPX, the RBN actually handled slightly more spots than in last year’s CQWW, which gives us a sense of what to expect next year in CQWW.
Perhaps more importantly for the loading of the system, we topped 100 simultaneous Skimmers during the weekend, and actually had 114 unique Skimmers contribute  during that period.  As far as hardware is concerned, we’re in a period of watchful waiting.  At some point the database server will max out, probably necessitating separating it from the web server, but we seem to have a little way to go yet.  Meanwhile, Nick and Felipe are working on a new set of statistical tools that should enable everyone to get the numbers he needs from the system in near real time.  We’re optimistic that usership will continue to grow.

Stay tuned … who knows when the next good idea will come along?  And if you’d like to join us, drop us an e-mail and tell us what you have in mind.

73, Pete Smith, N4ZR