Monday, November 1, 2010

Finally, a "DX Cluster" for Contesters - how to use the RBN in contests

As we approach the big CW contests of the season, I thought that Assisted/Unlimited contesters might appreciate a few tips on how to make the best use of the Reverse Beacon Network's Telnet feed (, port 7000).

As I've said before, the RBN is uniquely fitted to use by contesters, because its 40 or more stations scattered worldwide spot every running station, wherever the station is being heard. Stations are re-spotted every 10-11 minutes if they stay on the same frequency, or immediately if they change frequency more than a few hundred Hz. The result is an all-band snapshot of activity on every band, delivered in real time. Picture that on Sunday afternoon in Sweepstakes, or anytime during the CQWW DX contest. Is 10 meters open? As soon as one station calls CQ, and is heard by CW Skimmer at one or more of the Reverse Beacon Network stations, it will be spotted. You should never have to miss that rare opening again.

Now obviously, the volume of RBN spots will be tremendous, and could easily overwhelm you (or your logging program). The first thing to do, to manage this, is to filter spots at the Telnet node. K4TD, who generously hosts the node, uses DX Spider cluster software. This software lets you set filters with great precision, so that, for example, you can tell the node only to send you spots from a given continent, or country, call area, or even state. I find it most useful to limit the RBN spots I receive to those generated by stations nearby, because I can pretty much count on being able to hear everything they spot.

DX Spider's filter commands are quite different from those used by AR-Cluster. You can either learn the syntax or, as I did, download VE7CC's excellent CC User ( This software translates your wishes to commands and "tells" DX Spider what to do. You do *not* have to use CC User as an intermediate step between the telnet node and your logging program. Instead, once you've set the filters, you can shut it down, start your logging program, and you're ready to go.

Two more hints for operators using the RBN. Most contest loggers have a setting for "packet spot timeout", or something similar, that removes spots from the bandmap when they get too old. Because of RBN's unique re-spotting capability, there is no reason to have the timeout set to more than 15 minutes - if the station is still there, it will be spotted again, and your bandmap won't be clogged with obsolete spots.

And finally, if you want to make sure that you're spotted by the RBN, then once in a while, even if you're running fast, send "CQ" or "TEST" as a part of your end-of-QSO transmission. CW Skimmer isn't perfect at determining which stations are running and which are S&P - it has trouble with runners who only sign their calls at the end of each contact - but this way, you can help it "notice" you.

See you on the air.

73, Pete N4ZR

1 comment:

  1. Thanks Pete Yes this is a revolution
    In a few CQ knowing how the band is doing.
    But what about the selfspotters or friends of a contest station advertising they are out of job now.. But this is more honest.
    Last MM contest it was real good on 20M 2 CQ's and the spots streamed down the N1MM info screen
    From ZL VK USA etc etc amazing